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c#visual-studiovisual-studio-debugging

Can I find out the return value before returning while debugging in Visual Studio?

Take the following function:

DataTable go() {
    return someTableAdapter.getSomeData();
}

When I set a breakpoint in this function, is there a possibility to inspect the returned value? go() is directly coupled to a datagrid in an .aspx page.

The only way to inspect the returned datatable is to use a temporary variable. However, that's a bit inconvenient. Isn't there another way?

Solution

  • Not that I know of. Note that if you do add a variable, it will get removed by the compiler in release builds anyway...

    Update: This functionality has been added to VS2013. You can see the return values in the autos windows or use $ReturnValue (or $ReturnValue1 or $returnvalue, depending on the VS version) in the watch/immediate window.

    The value can only be seen directly after returning from the function, thus the easiest way to access it is by putting a breakpoint on the function call and step over (F10) the call.

    Update for VS2015: boo! unfortunately, it doesn't appear to be in VS2015 (devenv v14)
    Update for VS2017: it's back. (devenv v15)
    Update for VS2022: In Visual Studio 2022 the name $ReturnValue in watch window works, but it needs to be added to the watch window BEFORE "return" statement is hit, not after. (according to Andrew)