To make a decision in your ASP program to execute certain code if some condition is True an If Statement is used
Because VBScript is the default language to program in ASP, when you program an ASP If Statement it is actually the same as programming a VBScript If Statement.
If Statement Syntax
There is a slight difference between ASP's If Statement and the If Statement implementation in most other languages.
There are no brackets, or curly braces, nor are there any parenthesis.
Rather the beginning of the code to be executed in the If Statement when its true is marked with Then and the end of the If Statement is plainly marked with End If
.
Below is an example of If Statement that will always be True
ASP Code:
<%
Dim myNum
myNum = 6
If myNum = 6 Then
Response.Write("Variable myNum = 6")
End If
%>
O/P:
Variable myNum = 6
Note:
In our If Statement,you might notice that the "=" operator is used to both set the value of myNum to 6 at first, then it is used to compare myNum to 6 .
In ASP,this dual use of the equals operator is confusing to many,
but it might help you to remember that you cannot set the value of variables within If Statements, which means that the "=" can only compare!
ASP - If Else Conditional Statement
Sometimes when the If Statement is True you might want to execute some code and some different code when it is False.
Just like other programming languages, in ASP with the use of the Else keyword you can do this
Below is an example in which Else portion of the If Statement is always executed as the given condition will always be false
ASP Code:
<%
Dim myNum
myNum = 23
If myNum = 6 Then
Response.Write("Variable myNum = 6")
Else
Response.Write("**Variable myNum = " & myNum)
End If
%>
O/P:
**Variable myNum = 23
ASP - ElseIf Conditional Statement
Whenever at a time you will want to check for multiple conditions but with a normal If Statement you can only check one condition,
You can do this with ElseIf in ASP, which is the name given to an If Statement that depends on another If Statement.
Think about it in plain english: If some condition is true Then do this ElseIf second condition is true Then do this, etc.
In other programming languages,you may have used the ElseIf condition statement , but if not just know that you cannot have an ElseIf statement without first having an if statement.
Below is an example in which second if statement (elseif) is always true.
ASP Code:
<%
Dim myFastfood
myFastfood = "JBox"
If myFastfood = "McD's" Then
Response.Write("Happy Meal Por Favor!")
ElseIf myFastfood = "JBox" Then
Response.Write("Two tacos please!")
Else
Response.Write("Foot-long turkey sub.")
End If
%>
O/P:
Two tacos please!
Share And Enjoy:These icons link to social bookmarking sites where readers can share and discover new web pages.
Keywords:
asp if statement response.write, asp if statement string,
asp if statement dim, asp tutorial
