js restricts the text box to only input numbers (regular expression)_form effects

Okay, let’s get down to business. By the way, I found many ways to limit the text box on the Internet, but none of them were satisfactory, so I had to practice it myself. Practice brings true knowledge. This sentence is correct.

Copy code The code is as follows:

function chkPrice(obj){
obj.value = obj.value.replace(/[^d.]/g,"");
//Must ensure that the first digit is a number instead.
obj.value = obj.value.replace(/^ ./g,"");
//Guarantee that only one appears, not multiple.
obj.value = obj.value.replace(/.{2,}/g,".");
//Guaranteed. It will only appear once and not more than twice
obj.value = obj.value.replace(".","$#$").replace(/./g,"" ).replace("$#$",".");
}
function chkLast(obj){
// If illegal characters appear, intercept them
if(obj.value.substr ((obj.value.length - 1), 1) == '.')
obj.value = obj.value.substr(0,(obj.value.length - 1));
}

The following is the text box that needs to be called:

Copy the code The code is as follows:

<input type="text" name="txtFee" id="txtFee" class="common" onkeyup="chkPrice(this);" onblur="chkLast(this)" onpaste="javascript: return false;"/>

The last one: onpaste="javascript: return false;" is to disable the "Paste" menu of the right mouse button, which can prevent the right mouse button or Ctrl V from pasting illegal Data, hehe.

I have only tested the above JS in the IE8 environment. If you have any ideas or questions, please leave a message.