W3Schools.com

ASP.NET Razor - C# 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(var i = 10; i < 21; i++)
    {<p>Line @i</p>}
</body>
</html>

Run example »

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>
@foreach (var x in Request.ServerVariables)
    {<li>@x</li>}
</ul>
</body>
</html>

Run example »

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>
@{
var i = 0;
while (i < 5)
    {
    i += 1;
    <p>Line #@i</p>
    }
}
</body>
</html>

Run example »

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

@{
string[] members = {"Jani", "Hege", "Kai", "Jim"};
int i = Array.IndexOf(members, "Kai")+1;
int len = members.Length;
string x = members[2-1];
}
<html>
<body>
<h3>Members</h3>
@foreach (var person in members)
{
<p>@person</p>
}
<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>

Run example »

W3Schools Certification

W3Schools' Online Certification

The perfect solution for professionals who need to balance work, family, and career building.

More than 10 000 certificates already issued!

Get Your Certificate »

The HTML Certificate documents your knowledge of HTML.

The CSS Certificate documents your knowledge of advanced CSS.

The JavaScript Certificate documents your knowledge of JavaScript and HTML DOM.

The jQuery Certificate documents your knowledge of jQuery.

The XML Certificate documents your knowledge of XML, XML DOM and XSLT.

The ASP Certificate documents your knowledge of ASP, SQL, and ADO.

The PHP Certificate documents your knowledge of PHP and SQL (MySQL).

WEB HOSTING
Best Web Hosting
PHP MySQL Hosting
Best Hosting Coupons
UK Reseller Hosting
Cloud Hosting
Top Web Hosting
$3.98 Unlimited Hosting
Premium Website Design
WEB BUILDING
Download XML Editor
FREE Website BUILDER
Best Website Templates Top CSS Templates
CREATE HTML Websites
EASY WEBSITE BUILDER
W3SCHOOLS EXAMS
Get Certified in:
HTML, CSS, JavaScript, XML, PHP, and ASP
W3SCHOOLS BOOKS
New Books:
HTML, CSS
JavaScript, and Ajax
STATISTICS
Browser Statistics
Browser OS
Browser Display
SHARE THIS PAGE