Linq to Db Sp

7/28/2019 Linq to Db Sp

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Linq ToADO.Net


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Linq to

DBStoreProcedure


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Linq to DBStored Procedure

LINQ to ADO.NET deals with data from external sources,basically anything ADO.NET can connect to. Any class that

implements IEnumerable can be queried with SQO(standard

query operators).

Its the simplest process in LINQ.

First you add LINQ To SQL class and Its extension is .dbml.

It will ask you to added into App_Code folder in Solution

Exploler and Click on OK Button.


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Linq to DBStored Procedure Now, Drag and drop tables and stored procedures on dbml page.

Drage the table here.

Drage stored procedures in this part

like insert,delete,update,display etc.


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Linq to DBStored Procedure

This designed page generates designer.cs class automatically.

You just use that class to access the functionalty on your aspx.cs page.

You have to create the object of class in .aspx page.

With the help of object, access the functions named as stored procedures

and pass parameters and get records from database. You can do all operations like insert,delete,update,retrive data using

LINQ.


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How to retrive data from database?

private void display()

{

EmployeeDataContext objDb = new EmployeeDataContext();

var q = objDb.selectAllEmployee();

GridView1.DataSource = q;

GridView1.DataBind();

}

Create object of EmployeeDataContext

class


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{





}

Create object of EmployeeDataContextclass

Call the stored procedure

With help of object


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{





}



With help of objectSet object to

Gridview

datasource


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{





}



With help of objectSet object to

Gridview

datasourceDataBind() method usedto bind data to gridview


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How to save data into database?

protected void btnSave_Click(object sender, EventArgs e)

{

using( DataClassesDataContext d1 = new DataClassesDataContext())

{

tb_Employee emp = new tb_Employee();

emp.sEmpName = txtName.Text;

emp.sAddress = txtAddress.Text;

emp.iMobileNo =Convert.ToInt64(txtMobile.Text);

emp.dSalary = Convert.ToDecimal(txtsalary.Text);

d1.tb_Employees.InsertOnSubmit(emp);

d1.SubmitChanges();

};

}


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How to Update data into database?

protected void btnUpdate_Click(object sender, EventArgs e)

{

DataClassesDataContext d1=new DataClassesDataContext();

d1.updateEmployee(Convert.ToInt32(HiddenField1.Value), txtName.Text,txtAddress.Text, Convert.ToInt64(txtMobile.Text),

Convert.ToDecimal(txtsalary.Text));

d1.SubmitChanges();

display();

}


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How to Delete data into database?

protected void btnDelete_Click(object sender, EventArgs e)

{

DataClassesDataContext d1 = new DataClassesDataContext();

d1.deleteEmployee(Convert.ToInt32(txtId.Text));

d1.SubmitChanges();

}


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How to display data in TextBoxs from Gridview

Step1

Step2:Field Window will be open and select CommandField from list and click

on Add Button.Step3: In the command Field, Show SelectButton set true.

Select Button will be displayed in gridview.

Step4:In SelectedIndexChanged event, type code

Step5:In code, GridView1.SelectedDataKey.Value is used to access the EmpIdor value of any column.

Step6: DataKeyNames property of Gridview should be set With column like

EmpId.

Click on arrow

select Edit Columns


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protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)

{


var q=

d1.selectEmployeeByEmpID(Convert.ToInt32(GridView1.SelectedDataKey.

Value));

foreach (var e1 in q)

{

HiddenField1.Value = e1.iEmployeeId.ToString();

txtId.Text = e1.iEmployeeId.ToString();

txtName.Text = e1.sEmpName;

txtAddress.Text = e1.sAddress;

txtMobile.Text = e1.iMobileNo.ToString();

txtsalary.Text = e1.dSalary.ToString();

}}

Call selectEmployeeByEmpIDstored procedure and pass datakey

to retrive data from database


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protected void GridView1_SelectedIndexChanged(object sender, EventArgs e)

{


var q=

d1.selectEmployeeByEmpID(Convert.ToInt32(GridView1.SelectedDataKey.

Value));

foreach (var e1 in q)

{

HiddenField1.Value = e1.iEmployeeId.ToString();

txtId.Text = e1.iEmployeeId.ToString();

txtName.Text = e1.sEmpName;

txtAddress.Text = e1.sAddress;

txtMobile.Text = e1.iMobileNo.ToString();

txtsalary.Text = e1.dSalary.ToString();

}}

Call selectEmployeeByEmpIDstored procedure and pass datakey

to retrive data from database

We get values from e1

object and Assign the

values to TextBoxes

Here we set empId

value in HiddenField1

control for used any

purpose .


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Linq to Db Sp

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