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JavaScript function for blacklisting characters in Unicode

17:18 18 August in Forms, General, JavaScript by Thomas

This is a handy little function I wrote today to help me out with a special text field. This field needs to accept number and letters only, no spaces and no other characters.  There is a var for each character I don't want the field to accept, and there is an array that holds all those vars for the checking loop at the end. Depending on how this field works out, I may need to restore a couple of characters, like '-' and '_', for which all I have to do is remove them from the array. My short hand for the characters may be a little vague, but you can find the Unicode for any character by using the Character Mapper in Windows. function noChars(e) { var keynum; var keychar; if(window.event) // IE { keynum = e.keyCode; } else if(e.which) // Netscape/Firefox/Opera { keynum = e.which; } keychar = String.fromCharCode(keynum); var space = /u0020/; var hash = /u0023/; var exc = /u0021/; var at = /u0040/; var dollar = /u0024/; var perc = /u0025/; var amp = /u0026/; var lper = /u0028/; var rper = /u0029/; var ast = /u002a/; var apos = /u0027/; var lbra = /u007b/; var pipe = /u007c/; var rbra = /u007d/; var cir = /u005e/; var hm = /u002d/; var us = /u005f/; var plus = /u002b/; var equal = /u003d/; var sqrl = /u005b/; var sqrr = /u005d/; var bakslash = /u005c/; var forslash = /u002f/; var dq = /u0022/; var colon = /u003a/; var semi = /u003b/; var ques = /u003f/; var per = /u002e/; var com = /u002c/; var ltag = /u003c/; var rtag = /u003e/; var tld = /u007e/; var acc = /u0060/; var charChecks = new Array(space,hash,exc,at,dollar,perc,amp,lper, rper,ast,apos,lbra,pipe,rbra,cir,hm,us,plus,equal,sqrl,sqrr,bakslash, forslash,dq,colon,semi,ques,per,com,ltag,rtag,tld,acc); var i; for (i=0; i < charChecks.length; i++)...