I am curious to know if there is a way to edit code in C# VS 2008 right when it has hit a breakpoint and I am walking thru the code... can I modify the code (such as the value in a variable or if my stepthrough line is about to hit an if statement ... can I modify the if statement....etc)? So far, I have to stop running VS, modify the code, then hit F5 and wait till the breakpoint is hit again.
When the breakpoint hits, and I am walking thru the code, and I attempt to edit the code, I get a message "Changes are not allowed when the debugger has been attached to an already running process of the code being debugged was optimized at build or run time."
There are only a few reasons I know of why Edit+Continue would be disabled in the Debug build. First and foremost is a 64-bit operating system, E+C only works for 32-bit code. Fix that with Project + Properties, Build tab, Platform Target = x86.
It is also an option that might have been turned off. Tools + Options, Debugging, Edit and Continue, Enable checkbox.
If this doesn't help, tell us a bit more about the kind of code you're debugging, the project template you selected when you started the project, how you got the debugger to break and a stack trace copied from the Call Stack window.
Yes, you can.
This is called Edit and Continue.
Note that it has some limitations.
EDIT: You need to switch to a debug build.
To modify the value of a variable or set a property while in break mode go to the Immediate window, set the new value, and hit return e.g.
strValue = "newValue"
Calendar1.Enabled = true
To retrieve a value you can just print it to the window e.e.
?strValue
?Calendar1.Enabled
- Stop running your app.
- Go to Tools > Options > Debugging > Edit and Continue
- Disable “Enable Edit and Continue”.
In response to this question:
can I modify the code (such as the value in a variable or if my stepthrough line is about to hit an if statement ... can I modify the if statement....etc)?
You cannot pop a new value into a variable directly, but what you can do is this:
- Set a breakpoint
- When that breakpoint is hit, click on the arrow in the left margin and drag it up to a previous line
- Now you can add code to change the circumstances (for example, you can set a variable to a new value, add/remove items from a collection, etc.)
See the other answers about enabling Edit & Continue -- in particular, make sure you're in Debug mode.
To solve this problem I did the following...
BUILD > CONFIGURATION MANAGER
Active solution configuration: DEBUG project context configuration: DEBUG
then TOOLS > OPTIONS > DEBUGGING > EDIT & CONTINUE make sure edit & continue is selected
then BUILD > CLEAN SOLUTION then BUILD > REBUILD SOLUTION
Then start debug, then pause, then your code should be editable
Below answer worked for me :
http://whyiamright.wordpress.com/2007/12/20/aspnet-edit-and-continue-in-visual-studio-2005/
The second point says - project-properties-web-> enable edit and continue.
thats it.
来源：https://stackoverflow.com/questions/2781060/editing-code-in-visual-studio-2008-in-debug-mode