Length limit of HTML textarea

Length limit of HTML textarea

Encoding in HTML

The length of input. Generally, maxlength is used.

When textarea is unavailable,

The following methods should be used:

Onkeyup = 'if (this. value. length> = 20) {event. returnvalue = false }'

Onkeydown cannot be used. The difference between them is that onkeyup occurs after the keyboard clicks and the input content is input to the page.

In this way, the value of this. value is meaningful, and onkeydown occurs before the content changes after the keyboard is clicked.