Error when using a conditional breakpoint on System.Type

问题

This is the function:

public void Init(System.Type Type) {
    this.Type = Type;
    BuildFieldAttributes();
    BuildDataColumns(FieldAttributes);
}

I've set a breakpoint on the first line (this.Type = Type) and I want to break when Type.FullName == "Malt.Organisation" so that's what I've entered in as the condition.

However the following error is displayed when the line is hit:

The condition for a breakpoint failed to execute. The condition was 'Type.FullName == "Malt.Organisation"'. The error returned was 'Inspecting the state of an object in the debuggee of type System.Type is not supported in this context.'

What (obvious) thing am I doing wrong?

PS. A workaround is to add this to the code:

if (Type.FullName == "Malt.Organisation") System.Diagnostics.Debugger.Break();

回答1:

In my case I was using Visual Studio 2013, NUnit 2.6.4, and attaching a debugger to a unit test session, and I was getting a similar message:

The condition for a breakpoint failed to execute. The condition was 'type.Name.Contains("FooBar")'. The error returned was 'Inspecting the state of an object in the debuggee of type System.Type is not supported in this context.'. Click OK to stop at this breakpoint.

This was caused by a missing feature in the new debug engine Microsoft had introduced, apparently. Following instructions from this msdn blogpost I got things to work. The instructions boil down to:

From the "Tools" menu open "Options"
On the left hand side pick "Debugging", "General"
Scroll all the way down to check "Use Managed Compatibility Mode"

This should switch to the legacy debug engine, which in my case allowed for expressions on Type in break point conditions. Note that you do need to restart your app or debugging session, obviously.

Disclaimer: I have no idea what other effects checking this option had. Personally, I turned it back off when I was done with the task that required it...

回答2:

You say that Type.FullName == "Malt.Organisation" causes it to break, have you tried this.Type.FullName == "Malt.Organisation"?

Another possibility, does the debugger think you are trying to invoke a static method with having the variable named Type like its class name? Does renaming the Type variable to something else fix it?

回答3:

I ran into this but when testing for IsInterface in a Web Application. Instead of enabling extra features in the debugger, I simply cheated.

bool blnIsInterface = tType.IsInterface;

//Insert breakpoint here...
if(blnIsInterface)
{
    ...
}

So in your case your could do something like

public void Init(System.Type Type) {
    bool blnBreak = Type.FullName == "Malt.Organisation";
    //insert breakpoint of blnBreak == true
    this.Type = Type;
    BuildFieldAttributes();
    BuildDataColumns(FieldAttributes);
}

It's a bit cumbersome but at least you won't have to worry about performance hits and enabling Native code debugging doesn't seem to be an option in Web Applications.

回答4:

I'm not sure about "Use Managed Compatibility Mode" solution described here - did not help me, but in my own case Project > Properties > Debug > Enable Native code debugging - must be unchecked.

Why - no clue currently.

Was using .net 4.5, vs2015, console application.

来源：https://stackoverflow.com/questions/32276732/error-when-using-a-conditional-breakpoint-on-system-type

标签

conditional-breakpoint