如何在带有嵌入式JS文件的服务器控件中使用<％= control.ClientID％>

I am creating a server control in a library project, which has javascript code, the javascript code need to get a button's ID, so I used <%= button.ClientID %>. Then I embed the javascript code as a file in the library project and use ScriptManager to add the script in CreateChildControls(). I am creating a server control in a library pro