Allow only numbers using JavaScript for textboxes -

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• how allow alpha numeric chars javascript 2 answers

i new javascript. have created form submits details database. have different textboxes, need accept only letters , allow numbers.

i got code while doing research, code tells me of invalid pattern. can me code allows only letters. tried modify code takes letters failed.

function f_check_lett(form){    //only letters , numbers allowed        var text = form.bucketname.value;     alert(text);      var filter = /^[a-za-z0-9]+$/;     if (filter.test(text)) {         form.submit();      } else {         form.bucketname.select();         alert("only allow letters , numbers!");     } }   

use filter

var filter = /^[a-za-z]+$/; 

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in filter [a-za-z0-9] accept character of: 'a' 'z', 'a' 'z', '0' '9'

since need letters, remove 0-9 filter.