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I know the JavaScript that restricts entering some special characters or number, etc using charcode and ascii value.

Is there anyway that I can block people entering any other language (I mean alphabet) expect English? More specifically how can I block people entering Chinese or some other non English alphabet name in the textbox and make them strictly enter only English alphabet name?

Thanks

Karthik Malla
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3 Answers3

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I use this function to remove special characters from input

function removeSpecials(evt) {
var input = document.getElementById("myinput");
var patt = /[^\u0000-\u007F ]+/;
setTimeout(function() {
     var value = input.value;
     input.value = value.replace(patt,"");
 },100);

}

The point is: I create a pattern to detect all special characters

var patt = /[^\u0000-\u007F ]+/;;

and I replace the input value

value.replace(patt,"");

Here is a FIDDLE

nanndoj
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  • This code is supposed to remove only form last typed char. I will change the example to remove all from the input. You have to use replace instead – nanndoj Jan 26 '15 at 01:16
1

Easiest way to block all non-ascii inputs would probably be

/^[\x00-\xff]+$/.test(input);

This expression will return true if input is composed of purely ascii characters.

It will return false if any non-ascii character is found.

You can adjust the range of accepted ascii characters to meet your needs. \x00-\x55 includes ascii char codes 0-255

Mulan
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0

You can easily restrict the user to a specific character set by checking their input with something like inputString.match(/^[A-Za-z]+$/). That will catch languages like Chinese, though there are plenty of languages which share almost the same alphabet as English and thus cannot be easily blocked.

Ixrec
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  • Thanks mate, no problem. My main goal is to block languages like Chinese, Japanese, etc. which doesn't follow English alphabet. – Karthik Malla Jan 26 '15 at 00:56