JavaScript determines whether the textarea value is empty and gives the appropriate hints _javascript tips

We often use JavaScript in web design to determine whether the user entered the legitimate data, if the user did not input data to give the corresponding prompts, then how to judge? Here we introduce the method of using JavaScript to judge whether the textarea value is empty.

The JavaScript functions are given below:

if (document.getElementById ("Htmer"). value== ') {alert ("Please enter the content!"); return false;}

Note that the red part of the code above = = "", is a single quotation mark instead of double quotes, which can reduce a lot of unnecessary trouble.