Master Pages Controls Id After Rendered

In my asp.net projects there is a master page and t开发者_如何学运维here is a control on Contentplaceholder1. Changing this control's id after rendered like "ctl00_Contentplaceholder1_control" in my local. But at the server its changing like "Contentplaceholder1_control". When i used documents.getelelentbyid('ctl00_Contentplaceholder1_control') js function, its working on my local but not working at the server. So why disappearing "ctl00_" when app runs at the server?

Edit:

Why doesn't the server side control id contains "ctl00_" after rendered?

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Use the server side property ClientID to get the appropriate ID or if you are using .NET 4, use ClientIDMode.

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Why don't you use ClientIDMode to make static IDs? Which version of .NET Framework are you using?

Another options (for older versions) is to wrap your .NET control in a div with static id, then use jQuery like this:

 var wrapper = $('#wrapperDivId');
 var control = wrapper.find('typeOfControl')[0];

This way, no matter of how your control's id is rendered, you can always have access to it.

For example, TextBoxes render to <input type='text' />. Now you can wrap your text box inside a div like this:

 <div id='wrapper'>
      <asp:TextBox ID='firstName' runat='server' />
 </div>

Now, no matter of the client id, you can get your textbox at client side using:

 $('#wrapper input')

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You should do like...

documents.getElelentbyid('<%=ControlID.ClientID %>') 

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document.getElementById("<%= control.ClientID %>");

that is much safer and better approach than hard-coding client id.

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Answer is here.

My hosting server changed their asp.net servers to asp.net 4 server. So my controls rendered without "ctl00_". I compiled my .net 3.5 project to the .net 4 and I changed web.config file like this.

Now its working.