MVC Interview questions and answers

8/9/2019 MVC Interview questions and answers

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100 important MVC Interview Question

By

Shivprasad Koirala

AndSukesh Marla

Do not miss our 2 days ( Saturday and Sunday) full hands on MVC training ourse in Mum!aiall "22#$$%&2'%

ant to learn MVC online start from the !elo* youtu!e video

https+,,***-youtu!e-om,*ath.v/0p%nS1m&vk

Contents

What is MVC?

MVC is an arhitetural pattern *hih separates the representation and the user interation- 1t3s divided into three !roader setions4 5Model64 5Vie*6 and 5Controller6- Belo* is ho* eah one of them handles thetask-

7he 5Vie*6 is responsi!le for look and feel-

5Model6 represents the real *orld o!8et and provides data to the 5Vie*6-

7he 5Controller6 is responsi!le to take the end user re9uest and load the appropriate 5Model6 and5Vie*6-

Figure 6.1:- MVC (Model view controller)
https://www.youtube.com/watch?v=Lp7nSImO5vkhttps://www.youtube.com/watch?v=Lp7nSImO5vk


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Explain MVC application life cycle?

Note: - There is nothing as such called as MVC life cycle. I think lot of

people are obsessed with A!.N"T page life cycle and they think there is life

cycle in MVC as well. To be specific the MVC re#uest goes through $arioussteps of e%ecution and that&s what is ter'ed as MVC application life cycle.

Any *e! appliation has t*o main e:eution steps first understanding the re9uest and depending on thetype of the re9uest sending out appropriate response- MVC appliation life yle is not different it has t*omain phases first reating the re9uest o!8et and seond sending our response to the !ro*ser-

Creating the request object: - 7he re9uest o!8et reation has four ma8or steps- Belo* is the detaile:planation of the same-

te! 1 Fill route+ # MVC re9uests are mapped to route ta!les *hih in turn speify *hih ontroller andation to !e invoked- So if the re9uest is the first re9uest the first thing is to fill the route ta!le *ith routesolletion- 7his filling of route ta!le happens in the glo!al-asa: file-

te! " Fetch route:# Depending on the ;


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te! ' %ecute ction: # 7he 5ControllerAtion1nvoker6 determines *hih ation to e:euted ande:eutes the ation-

te! 6 $esult sent+ # 7he ation method e:eutes and reates the type of result *hih an !e a vie* result4 file result 4 ?S@ result et-

So in all there are si: !road steps *hih get e:euted in MVC appliation life yle-

Note :- In case you are not able to re'e'ber the abo$e steps during inter$iew

re'e'ber the acrony' (()C")*(ight (or )espect Can "$oke )e$olution+.

Is MVC suitable for both winows an web application?

MVC arhiteture is suited for *e! appliation than *indo*s- or *indo* appliation MV i-e- 5Modelvie* presenter6 is more applia!le-1fyouareusingandS0MVVMismoresuita!ledueto!indings-

What are the benefits of usin! MVC?

7here are t*o !ig !enefits of MVC+#

Separation of onerns is ahieved as *e are moving the ode !ehind to a separate lass file- Bymoving the !inding ode to a separate lass file *e an reuse the ode to a great e:tent-

Automated ;1 testing is possi!le !eause no* the !ehind ode (;1 interation ode) has moved toa simple-@>7 lass- 7his gives us opportunity to *rite unit tests and automate manual testing-

Is MVC ifferent from a " layere architecture?

MVC is an evolution of a layered traditional arhiteture- Many omponents of layered arhitetureare part of MVC- So !elo* is ho* the mapping goes-

Functionalit* # la*ered + tiered architecture Model view controller architecture

0ook and eel ;ser interfae- Vie*-

;1 logi ;ser interfae- Controller

Business logi ,validations Middle layer Model-


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Figure 6.":- # la*ered architecture

What is the latest version of MVC?

hen this note *as *ritten4 four versions *here released of MVC- MVC 4 MVC 24 MVC and MVC- So the latest is MVC &-

What is the ifference between each version of MVC?

Belo* is a detail ta!le of differenes- But during intervie* it3s diffiult to talk a!out all of them due totime limitation- So 1 have highlighted important differenes *hih you an run through !efore theintervie*er-

MVC 2 MVC 3 MVC 4

Client-Side Validation

Templated HelpersAreas

Asynchronous Controllers

Html.ValidationSummary Helper Method

DefaultValueAttribute in Action-Method

Parameters

Binding Binary Data with Model Binders

DataAnnotations Attributes

Razor

eadymade pro!ecttemplates

HTML ena!led templates

Support "or Multiple Vie#

$n%ines

&a'aScript and A(a)

Model Validation

"mpro#ements

AS*+,$T e! A*.

efreshed and moderni$ed defaultpro!ect templates

%ew mobile pro!ect template

Many ne# "eatures to support

mo!ile apps

&nhanced support for

asynchronous methods


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Model-Validator Pro#iders

%ew e'uireHttpsAttribute Action (ilter

)emplated Helpers

Display Model-*e#el &rrors

What are #$M% helpers in MVC?

=7M0 helpers help you to render =7M0 ontrols in the vie*- or instane if you *ant to display a=7M0 te:t!o: on the vie*4 !elo* is the =7M0 helper ode-

or hek!o: !elo* is the =7M0 helper ode- 1n this *ay *e have =7M0 helper methods for every=7M0 ontrol that e:ists-

What is the ifference between $M%'$ext(ox) vs $M%'$ext(ox*or)?

Both of them provide the same =7M0 output4 5=7M0-7e:tBo:or6 is strongly typed *hile

5=7M0-7e:tBo:6 isn3t-

Belo* is a simple =7M0 ode *hih 8ust reates a simple te:t!o: *ith 5CustomerCode6 as name-

Html.TextBox("CustomerCode")

Belo* is 5=tml-7e:tBo:or6 ode *hih reates =7M0 te:t!o: using the property nameECustomerCode6 from o!8et 5m6-

Html.TextBoxor(m => m.CustomerCode)

1n the same *ay *e have for other =7M0 ontrols like for hek!o: *e have 5=tml-ChekBo:6 and5=tml-ChekBo:or6-


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Explain the importance of MVC moel biners?

Model !inder maps =7M0 form elements to the model- 1t ats like a !ridge !et*een =7M0 ;1 and MVCmodel-

7ake the !elo* simple =7M0 form e:ample+#

Customer code :-

Customer name :-

@o* this form needs to fill the !elo* 5Customer6 lass model- 1f you see the =7M0 ontrol name theyare different from the lass property name- or e:ample =7M0 te:t!o: ontrol name is 5CCode6 and thelass property name is 5CustomerCode6- 7his mapping ode is *ritten in =7M0 !inder lasses-

pubic cass Customer

!

pubic strin CustomerCode ! et# set# $

pubic strin CustomerName ! et# set# $

$

7o reate a model !inder *e need to implement 51ModelBinder6 interfae and mapping ode needs to !e*ritten in the 5BindModel6 method as sho*n in the !elo* ode-

pubic cass Customer%inder : &'ode%inder

!

pubic ob(ect %ind'ode)ControerContext controerContext* 'ode%indinContext

bindinContext+


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!

,ttpe.uest%ase re.uest = controerContext,ttpContexte.uest#

strin strCustomerCode = re.uest0ormet)"CCode"+#

strin strCustomerName = re.uest0ormet)"CName"+#

return ne2 Customer

!

CustomerCode = strCustomerCode*

CustomerName = strCustomerName

$#

$

$

@o* in the ation result method *e need to use the 5ModelBinder6 attri!ute *hih *ill attah the !inder*ith the lass model-

pubic 3ctionesut SubmitCustomer)4'ode%inder)typeof)Customer%inder++5Customer ob(+

!

return 6ie2)78ispayCustomer+#

$

What are routin! in MVC?


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Where is the route mappin! coe written?

7he route mapping ode is *ritten in the 5glo!al-asa:6 file-

Can we map multiple +,%-s to the same action?

Fes 4 you an 4 you 8ust need to make t*o entries *ith different key names and speify the same ontrollerand ation-

#ow can we navi!ate from one view to other view usin! hyperlin.?

By using 5Ation0ink6 method as sho*n in the !elo* ode- 7he !elo* ode *ill reate a simple ;


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Figure 6.#:- di,,erence between te!data viewdata and viewbag

/e! data: -=elps to maintain data *hen you move from one ontroller to other ontroller or from oneation to other ation- 1n other *ords *hen you rediret45tempdata6 helps to maintain data !et*een thoseredirets- 1t internally uses session varia!les-

View data: - =elps to maintain data *hen you move from ontroller to vie*-

View 0ag: -1t3s a dynami *rapper around vie* data- hen you use 5Vie*!ag6 type asting is not

re9uired- 1t uses the dynami key*ord internally-

Figure 6.&:-d*naic e*word


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ession variables+ # By using session varia!les *e an maintain data from any entity to any entity-

2idden ,ields and 2/M3 controls+ # =elps to maintain data from ;1 to ontroller only- So you an senddata from =7M0 ontrols or hidden fields to the ontroller using S7 or G>7 =77 methods-

Belo* is a summary ta!le *hih sho*s different mehanism of persistene-

Maintains data between View4ata+View0ag /e!4ata 2idden ,ields ession

Controller to Controller @o Fes @o Fes

Controller to View Fes @o @o Fes

View to Controller @o @o Fes Fes

What is life of &$emp4ata) ?

57empData6 is availa!le for the urrent re9uest and in the su!se9uent re9uest it3s availa!le depending on*hether 57empData6 is read or not-

So if 57empData6 is one read it *ill not !e availa!le in the su!se9uent re9uest-

What is the use of 5eep an ee. in &$emp4ata)?

ne 57empData6 is read in the urrent re9uest it3s not availa!le in the su!se9uent re9uest- 1f *e *ant57empData6 to !e read and also availa!le in the su!se9uent re9uest then after reading *e need to all5Keep6 method as sho*n in the ode !elo*-

7Tem!4ata18M54ata92-

Tem!4ata.:ee!(8M54ata9)-

7he more shortut *ay of ahieving the same is !y using 5eek6- 7his funtion helps to read as *elladvies MVC to maintain 57empData6 for the su!se9uent re9uest-

stri'; str = Tem!4ata.+eek("Td").Totri';()-

What are partial views in MVC?

artial vie* is a reusa!le vie* (like a user ontrol) *hih an !e em!edded inside other vie*-or e:ample let3s say all your pages of your site have a standard struture *ith left menu4 headerand footer as sho*n in the image !elo*-


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Figure 6.':- !artial views in MVC

or every page you *ould like to reuse the left menu4 header and footer ontrols- So you an goand reate partial vie*s for eah of these items and then you all that partial vie* in the mainvie*-

#ow i you create partial view an consume the same?

hen you add a vie* to your pro8et you need to hek the 5Create partial vie*6 hek !o:-


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Figure6.6:-create!artialview

ne the partial vie* is reated you an then all the partial vie* in the main vie* using5=tml-


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!u3lic stri'; CustomerCode

set-

;et-

1n order to display the validation error message *e need to use 5ValidateMessageor6 method *hih!elongs to the 5=tml6 helper lass-

m.CustomerCode)%>

0ater in the ontroller *e an hek if the model is proper or not !y using 5ModelState-1sValid6 propertyand aordingly *e an take ations-

!u3lic /ctio'esult +ostCustomer(Customer o36)

i (Modeltate.@s#alid)

o36.ae()-

retur' #ie$("Tha'ks")-

else

retur' #ie$("Customer")-

Belo* is a simple vie* of ho* the error message is displayed on the vie*-


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Figure 6.5:- validations in MVC

Can we isplay all errors in one !o?

Fes *e an4 use 5ValidationSummary6 method from =7M0 helper lass-


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1f you have reated the model o!8et yourself you an e:pliitly all 57ry;pdateModel6 in yourontroller to hek if the o!8et is valid or not-

Tr5*!dateModel(Ne$Customer)-

1n ase you *ant add errors in the ontroller you an use 5AddModel>rror6 funtion-

Modeltate./ddModel?rror("irstName" "This is m5 sererDside error.")-

#ow can we enable ata annotation valiation on client sie?

1t3s a t*o#step proess first referene the neessary 89uery files-

Explain 6reas in MVC?

Areas help you to group funtionalities in to independent modules thus making your pro8et moreorganiHed- or e:ample in the !elo* MVC pro8et *e have four ontroller lasses and as time passes !yif more ontroller lasses are added it *ill !e diffiult to manage- 1n !igger pro8ets you *ill end up *ith""3s of ontroller lasses making life hell for maintenane-


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1f *e an group ontroller lasses in to logial setion like 51nvoiing6 and 5Aounting6 that *ouldmake life easier and that3s *hat 5Area6 are meant to-

Fou an add an area !y right liking on the MVC solution and liking on 5Area6 menu as sho*n in the

!elo* figure-

1n the !elo* image *e have t*o 5Areas6 reated 5Aount6 and 51nvoiing6 and in that 1 have put therespetive ontrollers- Fou an see ho* the pro8et is looking more organiHed as ompared to the previousstate-


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What is ra7or in MVC?

1t3s a light *eight vie* engine- 7ill MVC *e had only one vie* type i-e-ASI4


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Explain the ifference between layout an master pa!es ?

0ayout are like master pages in AS-@>7 e! form- Master pages give a standard look and feel for e!form vie*s *hile layout gives standard look and feel or ats like a template for raHor vie*s-

#ow to apply layout to ,a7or views?

So first *e need to reate a template file as sho*n in the !elo* ode-

7e'derectio'("Header")

7e'derBod5()

7e'derectio'("ooter")

And then apply this template to the vie* as sho*n !elo* and display data in those respetive setions-

7La5out = "ie$s&4eaultA&La5out+a;eA.cshtml"-

This is 3od5

7sectio' ooterCo!5ri;ht KADKA

7sectio' HeaderOelcome to m5 site

Explain the concept of 2caffolin!?

Note PD 4o 'ot ;et scared $ith the $ord. @ts actuall5 a er5 sim!le thi';.

Saffolding is a tehni9ue in *hih the MVC template helps to auto#generate C


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1t reates ontroller ode4 vie* and also ta!le struture as sho*n in the !elo* figure-


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What oes scaffolin! use internally to connect to atabase?

1t uses >ntity frame*ork internally-


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#ow can you o authentication an authori7ation in MVC?

Fou an use *indo*s or forms authentiation for MVC-

#ow to implement winows authentication for MVC?

or *indo*s authentiation you need to go and modify the 5*e!-onfig6 file and set authentiation modeto *indo*s-

7- So the first step is to setauthentiation mode e9ual to forms- 7he 5login;rl6 points to a ontroller here rather than page-


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e also need to reate a ontroller *here *e *ill hek the user is proper or not- 1f the user is proper *e*ill set the ookie value-

!u3lic /ctio'esult Lo;i'()

i ((euest.orm1"txt*serName"2 == "hi") UU (euest.orm1"txt+ass$ord"2

== "hi7AKR"))

orms/uthe'ticatio'.et/uthCookie("hi"true)-

retur' #ie$("/3out")-

else

retur' #ie$("@'dex")-

All the other ations need to !e attri!uted *ith 5AuthoriHe6 attri!ute so that any unauthoriHed user if hemakes a all to these ontrollers it *ill rediret to the ontroller ( in this ase the ontroller is 50ogin6)*hih *ill do authentiation-

1/uthoriFe2

+u3lic/ctio'esult 4eault()

retur' #ie$()-

1/uthoriFe2

!u3lic/ctio'esult /3out()

retur' #ie$()-

#ow to implement 69ax in MVC?

Fou an implement A8a: in t*o *ays in MVC+#


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A8a: li!raries

?9uery

Belo* is a simple sample of ho* to implement A8a: !y using 5A8a:6 helper li!rary- 1n the !elo*ode you an see *e have a simple form *hih is reated !y using 5A8a:-Beginorm6 synta:-

7his form alls a ontroller ation alled as 5getCustomer6- So no* the su!mit ation lik *ill!e an asynhronous a8a: all-

1script language6a$ascript5

function 7nuccess*data8+

9

,, 0o so'ething here

1,script5

1di$512

$ar A6a%7pt new A6a%7ptions97nuccess7nuccess4

25

12 using *A6a%.;egin(or'*getCusto'er/MyA6a%/A6a%7pt++ 9 25

1input idt%tCusto'erCode typete%t ,51br ,5

1input idt%tCusto'erNa'e typete%t ,51br ,5

1input idub'it


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funtion on the ontroller 4 !elo* is the ode for the same- ne the ontroller responds this data isdisplayed in the =7M0 D1V tag !y name 5DateDiv6-

1span id0ate0i$ ,5

12:

A6a%.Action=ink*>et 0ate/>et0ate/

new A6a%7ptions 9?pdateTargetId 0ate0i$ +

25

Belo* is the ontroller ode- Fou an see ho* 5GetDate6 funtion has a pause of " seonds-

public class 0efault8Controller : Controller

9

public string >et0ate*+

9

Thread.leep*8@@@@+4

return 0ateTi'e.Now.Totring*+4

7he seond *ay of making A8a: all in MVC is !y using ?9uery- 1n the !elo* ode you an see *e aremaking an a8a: S7 all to a ;et0ata*+

9

$ar url ,MyA6a%,getCusto'er4

.post*url/ function *data+

9

*Bt%tCusto'erCode+.$al*data.Custo'erCode+4

*Bt%tCusto'erNa'e+.$al*data.Custo'erNa'e+4

+


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What .in of events can be trac.e in 6:68 ?

Figure 6.7:- traced in 89

What is the ifference between &6ction,esult) an &View,esult)?

5Ation


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7here 2 kinds of results in MVC4 at the top is 5Ation


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- 1nspet the returned value-

- rovide e:tra data to the ation-

Fou an reate ation filters !y t*o *ays+#

1nline ation filter-

Creating an 5Ationilter6 attri!ute-

7o reate a inline ation attri!ute *e need to implement 51Ationilter6 interfae-7he 51Ationilter6interfae has t*o methods 5nAtion>:euted6 and 5nAtion>:euting6- e an implement pre#proessing logi or anellation logi in these methods-

public class 0efault8Controller : Controller / IAction(ilter

9

public Action)esult Inde%*Custo'er ob6+

9

return View*ob6+4

$oid IAction(ilter.7nAction"%ecuted*Action"%ecutedConte%t

filterConte%t+

9

Trace.Frite=ine*Action "%ecuted+4

$oid IAction(ilter.7nAction"%ecuting*Action"%ecutingConte%t

filterConte%t+

9 Trace.Frite=ine*Action is e%ecuting+4

7he pro!lem *ith inline ation attri!ute is that it annot !e reused aross ontrollers- So *e an onvertthe inline ation filter to an ation filter attri!ute- 7o reate an ation filter attri!ute *e need to inheritfrom 5AtionilterAttri!ute6 and implement 51Ationilter6 interfae as sho*n in the !elo* ode-

public class MyActionAttribute : Action(ilterAttribute / IAction(ilter

9

$oid IAction(ilter.7nAction"%ecuted*Action"%ecutedConte%t filterConte%t+

9

Trace.Frite=ine*Action "%ecuted+4


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$oid IAction(ilter.7nAction"%ecuting*Action"%ecutingConte%t filterConte%t+

9

Trace.Frite=ine*Action e%ecuting+4

0ater *e an deorate the ontrollers on *hih *e *ant the ation attri!ute to e:eute- Fou an see in the!elo* ode 1 have deorated the 5DefaultController6 *ith 5MyAtionAttri!ute6 lass *hih *as reatedin the previous ode-

GMyActionAttributeH

public class 0efault8Controller : Controller

9

public Action)esult Inde%*Custo'er ob6+

9

return View*ob6+4

Can we create our custom view en!ine usin! MVC?

Fes4 *e an reate our o*n ustom vie* engine in MVC- 7o reate our o*n ustom vie* engine *e need

to follo* steps+#0et3 say *e *ant to reate a ustom vie* engine *here in the user an type a ommand like5LDate7ime6 and it should display the urrent date and time-

te! 1+# e need to reate a lass *hih implements 51Vie*6 interfae- 1n this lass *e should *rite thelogi of ho* the vie* *ill !e rendered in the 5render6 funtion- Belo* is a simple ode snippet for thesame-

public class MyCusto'View : IView

9

pri$ate string (older!ath4 ,, 0efine where our $iews are stored

public string (older!ath

9

get 9 return (older!ath4

set 9 (older!ath $alue4


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public $oid )ender*ViewConte%t $iewConte%t/ yste'.I7.Te%tFriter

writer+ 9

,, !arsing logic 1dateTi'e5

,, read the $iew file

string str(ile0ata (ile.)eadAllTe%t*(older!ath+4

,, we need to and replace 1dateti'e5 dateti'e.now $alue

string str(inal str(ile0ata.)eplace*10ateTi'e5/

0ateTi'e.Now.Totring*++4

,, this replaced data has to sent for display

writer.Frite*str(inal+4

te! " :-e need to reate a lass *hih inherits from 5VirtualathroviderVie*>ngine6 and inthis lass *e need to provide the folder path and the e:tension of the vie* name- or instane forraHor the e:tension is 5shtml6 4 for asp: the vie* e:tension is 5-asp:6 4 so in the same *ay forour ustom vie* *e need to provide an e:tension- Belo* is ho* the ode looks like- Fou an see

the 5Vie*0oationormats6 is set to the 5Vie*s6 folder and the e:tension is 5-myvie*6-

public class MyView"ngine!ro$ider : Virtual!ath!ro$iderView"ngine

9

,, Fe will create the ob6ect of Mycusto'e $iew

public MyView"ngine!ro$ider*+ ,, constructor

9

,, 0efine the location of the View file

this.View=ocation(or'ats new stringGH 9 J,Views,98,

9@.'y$iew/ J,Views,hared,9@.'y$iew 4 ,,location and e%tension of our$iews

protected o$erride IView CreateView*ControllerConte%t

controllerConte%t/ string $iew!ath/ string 'aster!ath+

9


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$ar physicalpath

controllerConte%t.3ttpConte%t.er$er.Map!ath*$iew!ath+4

MyCusto'View ob6 new MyCusto'View*+4 ,, Custo' $iew engine

class

ob6.(older!ath physicalpath4 ,, set the path where the $iewswill be stored

return ob64 ,, returned this $iew paresing logic so that it can

be registered in the $iew engine collection

protected o$erride IView Create!artialView*ControllerConte%t

controllerConte%t/ string partial!ath+

9

$ar physicalpath

controllerConte%t.3ttpConte%t.er$er.Map!ath*partial!ath+4

MyCusto'View ob6 new MyCusto'View*+4 ,, Custo' $iew engine

class

ob6.(older!ath physicalpath4 ,, set the path where the $iews

will be stored

return ob64 ,, returned this $iew paresing logic so that it can

be registered in the $iew engine collection

te! #:-e need to register the vie* in the ustom vie* olletion- 7he !est plae to register the ustomvie* engine in the 5Vie*>ngines6 olletion is the 5glo!al-asa:6 file- Belo* is the ode snippet for thesame-

protected $oid Applicationtart*+

9

,, tepK :- register this ob6ect in the $iew engine collection

View"ngines."ngines.Add*new MyView"ngine!ro$ider*++4

L..

Belo* is a simple output of the ustom vie* *ritten using the ommands defined at the top-


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Figure6.11:-custoviewengineusingMVC

1f you invoke this vie* you should see the follo*ing output-

Figure 6.1":- out!ut

#ow to sen result bac. in :2; format in MVC?

1n MVC *e have 5?sonet+4

Belo* is the ?S@ output of the a!ove ode if you invoke the ation via the !ro*ser-

Figure 6.1#:- 8=> ,orat in MVC


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What is &Web6I)?

=77 is the most used protool-or past many years !ro*ser *as the most preferred lient !y *hih *e

an onsume data e:posed over =77- But as years passed !y lient variety started spreading out- e haddemand to onsume data on =77 from lients like mo!ile48avasripts4*indo*s appliation et-

or satisfying the !road range of lient 5S76 *as the proposed approah- Fou an read more a!out5S76 from C hapter-

5e!A16 is the tehnology !y *hih you an e:pose data over =77 follo*ing S7 priniples-

#ow oes WC* iffer from WE( 6I ?

?CF ?0 @A

Multi-!rotocol hosting =eavy *eight !eause of ompliatedSD0 struture-

0ight *eight4 only the neessaryinformation is transferred-

@rotocol 1ndependent of protools- nly for =77 protool

Forats 7o parse SA message4 the lientneeds to understand SD0 format-riting ustom ode for parsing SD0is a heavy duty task- 1f your lient issmart enough to reate pro:y o!8etslike ho* *e have in -@>7 (addreferene) then SA is easier toonsume and all-

utput of 5e!A16 are simple stringmessage4?S@4Simple IM0 format et- So*riting parsing logi for the same in veryeasy-

@rinci!les SA follo*s S#N speifiation- >B A1 follo*s S7 priniples- (leaserefer a!out S7 in C hapter)-

With WC* also you can implement ,E2$32o why


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Figure 6.1&:- i!leent ;?eb@A< in MVC

te! "+# ne you have reated the pro8et you *ill notie that the ontroller no* inherits from

OApiControllerO and you an no* implement OpostO4OgetO4OputO and OdeleteO methods of =77 protool-

public class ValuesController : ApiController

9

,, >"T api,$alues

public I"nu'erable1string5 >et*+

9

return new stringGH 9 $alue8/ $alue"T api,$alues,

public string >et*int id+

9

return $alue4

,, !7T api,$alues

public $oid !ost*G(ro';odyHstring $alue+

9

,, !?T api,$alues,

public $oid !ut*int id/ G(ro';odyHstring $alue+

9


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,, 0"="T" api,$alues,

public $oid 0elete*int id+

9

te! #:-1f you make a =77 G>7 all you should get the !elo* results-

Figure 6.1':- 2//@

#ow can we etect that a MVC controller is calle by 2$ or /E$ ?

7o detet if the all on the ontroller is 5S76 ation or a 5G>76 ation *e an use5


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2o how o we implement bunlin! in MVC ?

pen the 5BundleConfig-s6 from the 5AppQStart6 folder-

1n the 5BundleConfig-s6 add the ?S files *hih you *ant !undle in to single entity in to the!undles olletion- 1n the !elo* ode *e are om!ining all the 8avasript ?S files *hih aree:isting in the 5Sripts6 folder as a single unit in to the !undle olletion-

bundles.Add*new cript;undle*J,cripts,Mycripts+.Include*

J,cripts,.6s++4

Belo* is ho* your 5BundleConfig-s6 file *ill look like-

public class ;undleConfig9

public static $oid )egister;undles*;undleCollection bundles+

9

bundles.Add*new cript;undle*J,cripts,Mycripts+.Include*


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J,cripts,.6s++4

;undleTable."nable7pti'iOations true4

ne you have om!ined your sripts in to one single unit *e then to inlude all the ?S files in tothe vie* using the !elo* ode- 7he !elo* ode needs to put in the ASI or na!leptimiHations6 to true in the5!undleonfig-s6 file or else you *ill not see the !undling effet in the page re9uests-

;undleTable."nable7pti'iOations true4

Explain minification an how to implement the same ?

Minifiation redues the siHe of sript and CSS files !y removing !lank spaes 4 omments et-or e:ample !elo* is a simple 8avasript ode *ith omments-

,, This is test

$ar % @4

% % P 84

% %


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After implementing minifiation the 8avasript ode looks something as !elo*- Fou an see ho**hitespaes and omments are removed to minimiHe file siHe and thus inreasing performane-

$ar %@4%%P84%%


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Customer@ame 7:tCustomer@ame

Amount 7:tAmount

CustomerBuying0evelColor

#ow can we use two = multiple> moels with a sin!le view?

0et us first try to understand *hat the intervie*er is asking- hen *e !ind a model *ith a vie**e use the model dropdo*n as sho*n in the !elo* figure- 1n the !elo* figure *e an only seletone model-

But *hat if *e *ant to !ind 5Customer6 as *ell as 5rder6 lass to the vie*-

or that *e need to reate a vie* model *hih aggregates !oth the lasses as sho*n in the !elo*ode- And then !ind that vie* model *ith the vie*-

!u3lic class Cust,rder#M

!u3lic Customer cust = 'e$ Customer()-

!u3lic ,rder ,rd = 'e$ ,rder()-

1n the vie* *e an refer !oth the model using the vie* model as sho*n in the !elo* ode-


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What .in of lo!ic view moel class will have ?

As the name says vie* model this lass has the gel ode or onnetion ode *hih onnets thevie* and the model-

So the vie* model lass an have follo*ing kind of logis+#

Color trans,oration logic+ # or e:ample you have a 5Grade6 property in model and

you *ould like your ;1 to display 5red6 olor for high level grade4 5yello*6 olor for

lo* level grade and 5green6 olor of ok grade-

4ata ,orat trans,oration logic +# Four model has a property 5Status6 *ith 5Married6

and 5;nmarried6 value- 1n the ;1 you *ould like to display it as a hek!o: *hih is

heked if 5married6 and unheked if 5unmarried6-

ggregation logic: - Fou have t*o different Customer and Address model lasses and

you have vie* *hih displays !oth 5Customer6 and 5Address6 data on one go-

tructure downsiBing: -Fou have 5Customer6 model *ith 5ustomerCode6 and

5Customer@ame6 and you *ant to display 8ust 5Customer@ame6- So you an reate a

*rapper around model and e:pose the neessary properties-

What is the use of &6llow#$M%) an &ValiateInput) attributes?

hile *orking *ith MVC you may have notied that MVC ations doesn3t allo* posting =7M0values - 7his is done to avoid ross site sripting seurity issues-0ook at the follo*ing e:ample*here *e are trying to post =7M0 to the MVC ation-


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But you an !ypass this restrition !y using one of the follo*ing 2 attri!utes

) Validate1nput attri!ute at ontroller level or ation level

2) Allo*=tml attri!ute at Mode 0evel

Explain unobtrusive :ava2cript?

;no!trusive ?avaSript helps you to deouple presentation and !ehavior- Consider the !elo*!utton ode it has t*o parts one is the ;1 i-e- the !utton itself and seond is the !ehavior i-e-5Sho*Alert()6-


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1n other *ords the !utton is tied up *ith the 5Sho*Alert6 ation- 1t *ould !e great if *e oulddeouple the !ehavior from the !utton so that any other !ehavior an !e attahed *ith the !utton-

1input typebutton onclickhowAlert*+ idbtn ,5

1script5

function howAlert*+

9

alert*3ello+4

1,script5

0ook at this !utton ode you an see no ation is attahed *ith the !elo* !utton element-

1input typebutton idbtn ,5

Ation to the !utton is attahed on runtime as sho*n in the !elo* ode- 1f needed tomorro* *ean attah some other !ehavior *ith 5!tn6 !utton - So uno!trusive 8avasript is nothing !utdeoupling the presentation from the !ehavior-

1script5

function howAlert*+

9

alert*3ello+4

$ar el docu'ent.get"le'ent;yId*btn+4

el.onclick howAlert4

1,script5

Explain the nee of isplay moe in MVC?

Display mode displays vie*s depending on the devie the user has logged in *ith- So *e anreate different vie*s for different devies and display mode *ill handle the rest-

or e:ample *e an reate a vie* 5=ome-asp:6 *hih *ill render for the desktop omputersand=ome-Mo!ile-asp:for mo!ile devies- @o* *hen an end user sends a re9uest to the MVCappliation4 display mode heks the 5user agent6 headers and renders the appropriate vie* tothe devie aordingly-
http://www.codeproject.com/Articles/556995/Home.Mobile.aspxhttp://www.codeproject.com/Articles/556995/Home.Mobile.aspx


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#ow can we valiate usin! faceboo. or twitter accounts =MVC 6uth> ?

ne of the most !oring proess for an end user is registering on a site- Sometimes those longforms and email validation 8ust puts off the user- So ho* a!out making things easy !y validatingthe users using their e:isting fae!ook , t*itter , linkedin , et aounts- So the user usessomething *hih he already has *hile the site is assured that this user is a proper user-

7his is ahieved !y using MVC Auth (pen standard for authoriHation)-

;sing MVC auth is a three step proess+#


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@e:t step is to open 5AuthConfig-s6 and you *ill see lot of readymade ode to user your1D and Key- So use the appropriate method as per site and provide the 1D and Key-

7AuthFebecurity.)egisterMicrosoftClient*

clientId: /

clientecret: +4

7AuthFebecurity.)egisterTwitterClient*

consu'erQey: /

consu'erecret: +4

7AuthFebecurity.)egister(acebookClient*

appId: /

appecret: +4

7AuthFebecurity.)egister>oogleClient*+4

@o* if you run your appliation you should get a link to B login as sho*n in the !elo*sreen- So if you login in B it *ill rediret to your MVC appliation-


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What is new in MVC ?

Belo* are the ne* features in MVC & +#

ne AS-@>7

Attri!ute !ased routing

Asp-@et 1dentity

Bootstrap in the MVC template

Authentiation ilters

ilter overrides

@e* Saffolding system

MVC Interview questions and answers

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