A potentially dangerous request.form value is detected

The problem is that you submit a form that has an HTML string, such as when you enter HTML tags in a textbox, or if you use the HTMLEditor component in a page, the workaround is to disable validaterequest.

If you are. NET 4.0 or later, be sure to look at Method 3.

This method is applicable in both ASP. NET WebForm and MVC

Method 1:

Add this sentence to the header of the. aspx file:

<%@ page validaterequest="false"  %>

Method 2:

Modify the Web. config file:

<configuration>    <system.web>        <pages validaterequest="false" />    </system.web></configuration>

Because the validaterequest default value is true. Just set it to false.

Method 3:

Web. config adds

<system.web>    "2.0" /></ System.web>

Because the validation of 4.0 is enabled before HTTP beginrequest, the requested validation applies to all ASP. NET resources, ASPX pages, ashx pages, Web services, and some HTTP handlers.

[Turn]http://www.cnblogs.com/youring2/p/3559781.html

A potentially dangerous request.form value is detected