Bind the change event to the input file. It will be effective in the first execution, but will have no effect in subsequent executions
迷茫2017-05-19 10:43:38
Has the selected file changed since then? If it is still the original file, the change event will not be triggered.
巴扎黑2017-05-19 10:43:38
When the value of an element changes, the change event is triggered.
When used for select elements, the change event will occur when an option is selected;
When used for text fields, the change event will occur when the element is out of focus