asp.net - Control Attributes render Encoded on dot net 4 - how to disable the encoding?

Question

I have an issue in asp.net 4.

When I add an attribute on controls, then the render it encoded.

For example, when I type this code

txtQuestion.Attributes["onfocus"] = 
    "if(this.value == this.title)
{
   this.value = '';
   this.style.backgroundColor='#FEFDE0';
   this.style.color='#000000';
}";

I get render

onfocus="if(this.value == this.title){this.value = 
'';this.style.backgroundColor='#FEFDE0';
this.style.color='#000000';}"

And every ' hash been change to & #39;

Is there a way to disable this new future only on some controls ? or an easy way to make a custom render ?

My Fail tries

I have all ready try some thinks but I fail. For example this fails.

txtQuestion.RenderingCompatibility = new Version("3.5");

I also locate the point that this attributes renders and is on

public virtual void RenderBeginTag(HtmlTextWriterTag tagKey) function,

there every attribute have a flag if he wish to be encoded, but I do not know how can anyone set it or not.

One Work Around

In the asp net forum in the same question, there is a solution that change the global EncodeType - this is not the solution that I search for - and the person that give the solution say that this is not a great workaround, with potential security issues or other render issues.

Thank you all in advanced.

By Kervin

Until now Kervin found that Microsoft suggest instead use this command.

txtQuestion.Attributes["onfocus"] = 
    "if(this.value == this.title){this.value = '';this.style.backgroundColor='#FEFDE0';this.style.color='#000000';}";

Use this one.

    Page.ClientScript.RegisterExpandoAttribute(txtQuestion.ClientID, "onfocus", 
 "if(this.value == this.title){this.value = '';this.style.backgroundColor='#FEFDE0';this.style.color='#000000';}");

And what MS render, is on the end of the page, a script that add onfocus on this control using JavaScript. We can do that even by our self with jQuery and probably be more compatible.

This is a solution, but still I am wish to know if there is a way to just avoid the Attribute Encoding and let me do what I wish my way - not MS way.

Answer 1

Have you tried using this new ASP.NET 4 feature to make a custom encoder?