C＃WPF检查按钮图像是否已更新，然后再次更新

I'm working on making a memory game in C# using borders with images and changing their source. Changing the first source works correctly, however after the second flip I call a function to check if they match before flipping them to a correct or hidden image. I've been having an issue with the second image because the events I've tried call before the function has exited so the second image only shows the hidden image. Is there an event I can call to check if the image has loaded before exiting?I'm working on making a memory game in C# using