document.getElementById（'blah'）。value的行为不符合预期

Question

Is there any situation where I would have to set the focus on a input text first ( document.getElementById('the_input_text').focus() ) before I could set the value ( document.getElementById('the_input_text').value='123' ) in order for me to see the value (123) in the input text?

I'm only asking because I have to do that on this page that I'm working on in order for me to see the value in the input text.

Answer 1

No, there is no case where you need to focus the element first…unless there is some horribly-written, separate JavaScript repeatedly hard-setting the value until or unless focused.

You might try:

setTimeout(function(){
  document.getElementById('the_input_text').value='123'
},2000);

…to see if there is JS that was overriding your values after setting them.

I've tested to ensure that the HTML5 placeholder="..." attribute does not cause a problem with this.