Tips for js to trigger selectonchange events _ javascript skills

To trigger the onchange event of select or text, you must manually change the value of select or text, there is a good way to trigger the selectonchange event select or text onchange event through js. You need to manually (input through the keyboard) change the value of select or text to trigger the event, if you assign values to select or text in js, The onchang event cannot be triggered,
For example, after loading the page, you need to trigger an onChange event and use document. getElementById ("province "). value = "Hubei"; it is not acceptable to assign values to select or text directly. to manually trigger the onchange event, add the following statement after js assigns values to select.

Document. getElementById ("province"). fireEvent ('onchange') to implement,

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