C# Edit and Continue: error 4054
Error Message
Modifying a 'method | property | indexer | operator' which contains the 'yield return' or 'yield break' statement will prevent the debug session from continuing while Edit and Continue is enabled
This error occurs if you try to modify a method, property, indexer, or operator containing a yield return or yield break statement. For more information, see yield (C# Reference). Edit and Continue does not support this change during debugging.
Consider the following code:
class Program
{
private int[] items = { 1, 2, 3 };
System.Collections.Generic.IEnumerable<int> Range(int start, int end)
{
for (int index = start; index < end; index++)
{
yield return items[index];
}
}
static void Main()
{
Program p = new Program();
foreach (int item in p.Range(0, 2))
{
}
}
}
If you set a breakpoint on yield return items[index], then start debugging and try to add a local variable declaration int a = 10 in the Range method, this error occurs.
To correct this error
Undo the changes, and then continue debugging without the changes.
—or—
On the Debug menu, click Stop Debugging, then make the changes and start a new debugging session.
See Also
Reference
yield (C# Reference)
Supported Code Changes (C#)
Edit and Continue (Visual C#)