Both guarantee the default initial value of the text box when the page is opened, and the text box content does not disappear after the submit

Ensures that the default initial value is given to the text box when the page is opened, and the contents of the text box do not disappear after the submit
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Now there is a text box in order for the content to not disappear after submission, so I write:

However, I also intend to give this text box a default value when opening the page (you have to initialize a value to value), how are these two issues compatible?
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Jump page submission, you have to assign value to the text box
Ajax commits, does not assign the value of the text box to null.
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