onload event handler called when the image is loaded. onload=function means that after the image is loaded, call this onload time, which is the method you wrote yourself. This method is called event callback, or delegation. balabala...anything is fine
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onload event handler called when the image is loaded.
onload=function means that after the image is loaded, call this onload time, which is the method you wrote yourself. This method is called event callback, or delegation. balabala...anything is fine
onload is actually an asynchronous process