Tryit Editor v1.8

Source Code:
<!DOCTYPE html> <html> <head> <script> function imgError() { alert('The image could not be loaded.'); } </script> </head> <body> <img src="image.gif" onerror="imgError()"> <p>A function is triggered if an error occurs when loading the image. The function shows an alert box with a text. In this example we refer to an image that does not exist, therefore the onerror event occurs.</p> </body> </html>
Result:
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