ASP.NET Razor - VB Loops and Arrays
Statements can be executed repeatedly in loops.
For Loops
If you need to run the same statements repeatedly, you can program a loop.If you know how many times you want to loop, you can use a for loop. This kind of loop is especially useful for counting up or counting down:
Example
<html>
<body>
@For i=10 To 21
@<p>Line #@i</p>
Next i</body>
</html>For Each Loops
If you work with a collection or an array, you often use a for each loop.A collection is a group of similar objects, and the for each loop lets you carry out a task on each item. The for each loop walks through a collection until it is finished.
The example below walks through the ASP.NET Request.ServerVariables collection.
Example
<html>
<body>
<ul>
@For Each x In Request.ServerVariables
@<li>@x</li>
Next x</ul>
</body>
</html>While Loops
The while loop is a general purpose loop.A while loop begins with the while keyword, followed by parentheses, where you specify how long the loop continues, then a block to repeat.
While loops typically add to, or subtract from, a variable used for counting.
In the example below, the += operator adds 1 to the variable i, each time the loop runs.
Example
<html>
<body>
@Code
Dim i=0
Do While i<5
i += 1
@<p>Line #@i</p>
Loop
End Code
</body>
</html>Arrays
An array is useful when you want to store similar variables but don't want to create a separate variable for each of them:Example
@Code
Dim members As String()={"Jani","Hege","Kai","Jim"}
i=Array.IndexOf(members,"Kai")+1
len=members.Length
x=members(2-1)
end Code<html>
<body>
<h3>Members</h3>
@For Each person In members
@<p>@person</p>
Next person
<p>The number of names in Members are @len</p>
<p>The person at position 2 is @x</p>
<p>Kai is now in position @i</p>
</body>
</html>
