Decision statements in vb.netPresentation Transcript
Introduction Decision making statements in VB.NET are used to control the flow of a program by checking one or more conditions. There are 3 types, They are If … then If …. Then … else Select case
If .. then This statement is used to test a condition and execute a set of statements if the condition is true . If it is false, the statement which is next to the if … then structure is executed.
syntax If Condition Then One or more Visual Basic statementsEnd If
Example Dim mark as integer If mark>40 then Msgbox (“Pass”) End if
If … then … else This statement is used to test a condition and execute a set of statements if the condition is true and execute another set of statement if it is false.
Syntax If condition Then One or more statementsElse One or more statementsEndIf
Example Dim a AsIntegerDim b AsIntegera = 3b = 4If a > b Then MsgBox("a is greater then b")Else MsgBox("b is greater then a")EndIf
Select case statement The Select Case statement executes one of several groups of statements depending on the value of an expression. If your code has the capability to handle different values of a particular variable then you can use a Select Case statement. You use Select Case to test an expression, determine which of the given cases it matches and execute the code in that matched case.
Syntax Select Case expression Case value1 Statement 1 Case value2 Statement 2 Case value3 Statement 3 Case value4 . . . CaseElse StatementEnd Select
Example ' Examination Grades Dim grade AsStringPrivateSub Compute_Click() grade= txtgrade.Text Select Case grade Case "A" result.Caption="High Distinction" Case"A-" result.Caption="Distinction" Case"B" result.Caption="Credit" Case"C" result.Caption="Pass" CaseElse result.Caption="Fail" End Select EndSub