问题
In my application, I am reading the text of a window for the same process. I am using GetWindowText of User32.dll. But when it tries to call the method, I am getting the exception "An unhandled exception of type 'System.ExecutionEngineException' occurred in aaaa.exe". Where can I see the exact error. And why I am getting this exception.
My code is as below.
[DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
public static extern int GetWindowText(IntPtr hWnd,
[Out] StringBuilder lpString, int nMaxCount);
EnumDelegate enumfunc = new EnumDelegate(EnumWindowsProc);
private bool EnumWindowsProc(IntPtr win, int lParam)
{
StringBuilder sb = new StringBuilder();
GetWindowText(win, sb, 100);
if (sb.Length > 0)
{
// do something
}
}
回答1:
You are getting this exception because your GetWindowText() call corrupted the garbage collected heap. Easy to do when you pass a string instead of a StringBuilder or forget to initialize the StringBuilder.
The Right Way:
[DllImport("user32.dll", CharSet = CharSet.Unicode)]
private static extern bool GetWindowText(IntPtr hWnd, StringBuilder buffer, int buflen);
...
var sb = new StringBuilder(666);
if (GetWindowText(handle, sb, sb.Capacity)) {
string txt = sb.ToString();
//...
}
来源:https://stackoverflow.com/questions/2013310/an-unhandled-exception-of-type-system-executionengineexception-occurring-when