Use Javascript to determine whether the image exists, and if it does not exist, display the code of the default image_javascript skills

Use the onerror event of the image object to judge. If an error occurs, replace the src of the image object with the URL of the default image.

The following is the judgment through js
Use javascript to judge whether the specified image file exists:
For example, judge this picture Whether the address exists.
If it does not exist, re-detect the image every few seconds. If the address is valid, it will prompt that the address is valid

The above returns true if the image exists

If the image exists, return GIF89aX

Because the picture does not exist, return that the picture does not exist!