java script validation

Question

Hi Please give the java script codewhich i have to apply in my text box onkeypressevent. that should restrict the numbers and special character but should allow 4 special character that is &_[] and .(dot)..... please send the code . Thanks Vibhakar singh

Sunny Sharma · Answer

Hi Vibhakar Use regex to allow/restrict keyboard input here is an example from qodo.co.uk: ------------------------------------------------------------------- /* code from qodo.co.uk */ // create as many regular expressions here as you need: var digitsOnly = /[1234567890]/g; var floatOnly = /[0-9\.]/g; var alphaOnly = /[A-Za-z]/g; function restrictCharacters(myfield e restrictionType) { if (!e) var e = window.event if (e.keyCode) code = e.keyCode; else if (e.which) code = e.which; var character = String.fromCharCode(code); // if they pressed esc... remove focus from field... if (code==27) { this.blur(); return false; } // ignore if they are press other keys // strange because code: 39 is the down key AND ' key... // and DEL also equals . if (!e.ctrlKey && code!=9 && code!=8 && code!=36 && code!=37 && code!=38 && (code!=39 || (code==39 && character==')) && code!=40) { if (character.match(restrictionType)) { return true; } else { return false; } } } --------------------------------------------------------------------- You can check the example here: http://www.qodo.co.uk/blog/javascript-restrict-keyboard-character-input/ and check the demo here: http://www.qodo.co.uk/assets/files/uploads/javascript-restrict-keyboard-character-input.html HTH :)