title: ASP.NET: CS1519: Invalid token 'this' in class, struct, or interface member declaration
body: <p>When attempting to load in a browser an ASP.NET web form (.aspx page) that I'm working on, I get the following runtime error:</p>
  
  <blockquote>
    <p>Server Error in '/' Application.</p>
    
    <p>Compilation Error</p>
    
    <p>Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately. </p>
    
    <p>Compiler Error Message: CS1519: Invalid token 'this' in class, struct,
    or interface member declaration</p>
    
    <p>Source Error:</p>
    
    <p>Line 447:            #line default<br>
    Line 448:            #line hidden<br>
    Line 449:            this.@__PageInspector_EndRenderTracing(new
    object[] {<br>
    Line 450:                        @__w});<br>
    Line 451:
    this.@__PageInspector_BeginRenderTracing(new object[] {</p>
  </blockquote>
  
  <p>The code quoted in the error message doesn't appear in any of my own code.</p>
  
  <p>My project builds ok.</p>
  
  <p>What's the cause of this error?</p>