Input Dialog Box

An input dialog box can be used to obtain a single item of input from the user

Presents a window (dialog box) requesting input

Syntax: stringVar = InputBox(prompt, title)

Example of an Input Dialog BoxPrivate Sub cmdDisplay_Click()

Dim fileName As String, prompt As String, title As String

Dim houseNumber As Single, street As String

prompt = "Enter the name of the file containing the information."

title = "Name of File"

fileName = InputBox(prompt, title)

Open fileName For Input As #1

Input #1, houseNumber

Input #1, street

picAddress.Print "The White House is at"; houseNumber; street

Close #1

End Sub

After executing, an inputdialog box will pop up

Using Message Dialog Box for Output The message dialog box is used to

present a pop-up window containing information for the user

Syntax: MsgBox prompt, , title

Example of a Message Dialog Box

MsgBox “Nice try, but no cigar”, , “Consolation”

Stays on thescreen until the user presses OK

Formatting the Output:

Create easily readable output In the Print method, the spacing of the

output is controlled by the following devices:semicoloncommaTab function

Semicolons

The next value output is placed in the next column position.

Example:

picOutput.Print “Patrick”; ”Jon”

Output:

PatrickJon

Example of Semicolon

picOutput.Print “Patrick”; “ Jon”

Output Screen:

Patrick Jon

Space here

Space here

Example of Semicolon

picOutput.Print 100; -200; 300

Output Screen:

100 -200 300

One space

Two spaces

Commas

A comma in a Print method causes the next value output to be placed in the next available print zone.

Each print zone is 14 positions wide.

Using Commas

Example:

picOutput.Print “SEE”, ”YOU”, ”SOON”

Output Screen:

SEE YOU SOON

Column 1

Column 15

Column 29

Using Commas

A print zone can be skipped by typing consecutive commas

Example:

picOutput.Print “HOURLY”, , “PAY”

Output Screen:

HOURLY PAYColumn 29

Tab Function

Specifies the column where output will start

Use only semicolons with the Tab function Can only be used to advance the print

position (cannot move backwards)

Example of Tab Function

Example: picOutput.Print Tab(3); “Hi there!” ; Tab(25) ;“Bye!”

Output Screen:

Hi there! Bye!

Column 3

Column 25

Built-In Functions

Take one or more input values and return an output value

A means provided by Visual Basic for carrying out small, common tasks

Types of Built-In functionsNumeric functions (manipulate numbers)String functions (manipulate strings)

Numeric Functions

Rnd Returns a number between 0 and 1 (excluding 1)

Sqr(n) Returns the square root of the number n

Round(n,r) Returns the number n rounded to r decimal places

Int(n) Returns the greatest integer less than or equal to the number n

Example of Numeric Functions

Private Sub cmdEvaluate_Click() Dim n As Single, root As Single

n = 6.76 root = Sqr(n) picResults.Print root; Int(n); Round(n,1)End Sub

Output: 2.6 6 6.8

Commonly-Used String Functions

Function: Left(“Penguin”, 4)

Purpose: Returns the number of characters specified, starting at the beginning of the string

Commonly-Used String Functions

Function: Right(“Cork City”, 4)

Purpose: Returns the number of characters specified from the end of the string

Commonly-Used String Functions

Function: Mid(“Commissioner”, 4, 3)

Purpose: Returns the substring starting at the position indicated by the first number and continuing for the length specified by the second number

Commonly-Used String Functions

Function: UCase(“Yes”)

Purpose: Converts any lowercase letters in a string to uppercase

String-Related Numeric Functions

Function: InStr(“John Smith”, “m”)

Purpose: Searches for the first occurrence of one string in another and gives the position at which the string is found

String-Related Numeric Function

Function: Len(“John Smith”)

Purpose: Returns the number of characters in the string.

Format Functions

The format functions provide detailed control of how numbers, dates, and strings are displayed.

Examples FormatNumber (12345.678, 1) 12,345.6 FormatCurrency (12345.678, 2) $12,345.68 FormatPercent (.185, 2) 18.50% FormatNumber (1 + Sqr(2), 3) 2.414

Format Function

Format (expr, “@……..@”)

Purpose: The value of this function is the value of expr right justified in a field of n spaces, where n is the number of @ symbols.

Format Examples

Format(12345, “@@@@@”) 12345

Format(123, “@@@@@”) 123

Format(“123.4”, “@@@@@”) 123.4

FormatDateTime Example

FormatDateTime (“9-15-04”, vbLongDate)

Output: Monday, September 15, 2004

Rnd Function

Returns a random number from 0 to 1.

(excluding 1).

Example:

picBox.Print Int(6 * Rnd) + 1

Output: Displays a random integer from 1 through 6.