Operators , Functions and Options in VB.NET

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.NET

Operators, Functions ,Option

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Operators An operator is a symbol or other character

indicating an arithmetic operation that acts on one or more elements in an application.

That take one operand are called unary operators.

That take two operands are called binary operators.

Operators

Arithmetic ^, –, *, /, \, Mod, +

Assignment =, ^=, *=, /=, \=, +=, -=, &=

Comparison/Relational

=, <>, <, >, <=, >=, Like, Is

Concatenation &, +

Logical/bitwise Not, And, Or, Xor, AndAlso, OrElse

Miscellaneous operations

AddressOf, GetType

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Arithmetic\ is integer division./ is regular division.34 / 2.5 = 13.634 \ 2.5 = 17 (convert 2.5 into 2 then)^ exponent operator.2^4 = 16

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Assignment

=

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Comparison / Relational=Dim a, b As Integer a = 5 b = 10

If a = b Thenlogic…….

End If

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Comparison / Relational

If TypeOf btnIntDiv Is Button Then MsgBox("Hai") End If

Use the TypeOf...Is operator to determine whether a given object:

Is an instance of a given class

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Comparison / Relational

LikeDefined only for operands of type String.

The result is True if the first operand matches the pattern given in the second operand; False if not.

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Comparison / Relational

Dim ans As Booleanans = "F" Like "F" ans = "F" Like "f" ans = "F" Like "FFF" ans = "aBBBa" Like "a*a" ans = "F" Like "[A-Z]" ans = "F" Like "[!A-Z]" ans = "a2a" Like "a#a" ans = "aM5b" Like "a[L-P]#[!c-e]"

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Comparison / Relational

ans = "BAT123khg" Like "B?T*" ans = "CAT123khg" Like "B?T*"

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Logical /bitwise

AndAlso

Only And?AndAlso performs logical short-circuiting: if

the first operand of the expression is False, the second operand is not evaluated.

b = (93 > 67) AndAlso MyFunction()

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Logical /bitwiseOrElse

OR ?

OrElse performs logical short-circuiting: if the first operand of the expression is True, the second operand is not evaluated.

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Multiple statements in one line ( : )

x = 3 : y = 5 : z = 6

One statement in multiple lines ( _ )

name = "Mr." & " " & "Karna" & _ " " & "Bhavin" & " " & _ ", Trivedi"

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CommentComments are brief explanatory notes

added to code for the benefit of those reading it.

Comment ( )

Uncomment ( )

buttons on the Edit toolbar. REM:

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Option ExplicitUsed at file level to force explicit

declaration of all variables in that file.

On (Default)Enables Option Explicit checking.

Off Disables Option Explicit checking.

Default - Object type.

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Option ExplicitOption Explicit On

Dim MyVar As Integer

MyInt = 10

MyVar = 10

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Option StrictRestricts implicit data type conversions

OnGenerate an error

Off (Default)Compiler default is Option Strict Off if do not specify Option Strict in your code.

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Option Strict Dim MyVar As Integer

MyVar = 1000

'Attempting to convert to an Integer generates an error.

MyVar = 1234567890.9876542

MsgBox(MyVar)

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Object data typeDim objDb As Object

when you do not know at compile time what data type the variable might point to.

Can point to data of any data type,

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Object data typeWhatever data type it refers to, an Object

variable does not contain the data value itself, but rather a pointer to the value.

It always uses four bytes in computer memory, but this does not include the storage for the data representing the value of the variable.

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Object data typeThe Object data type is slower than using

explicit data types.

The code that uses the pointer to locate the data, Object variables holding value types are slightly slower to access than explicitly typed variables.

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IMP functions , constants

vbCrLf Carriage return/linefeed character combination.

vbNewLine Newline character. vbTab Tab character.

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IMP functions , constants

Space(Integer)

InputBox()

MsgBox()

MessageBox.Show()

Val()

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With…End Withwhen we want to set number of properties

and methods related with one control or object that time use with..end with block.

It executes series of statement related to one control or object

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With…End WithSyntax:

With objname

end With

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With…End With

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With…End WithWith MyLabel .Height = 200 .Width = 200 .Text = "Demo Label"End With

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