Very simple JavaScript code to restrict text box to have floating point number. Code is here-
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Untitled Page</title> <script type="text/javascript"> function restrict(val, e) { var keyChar; if (window.event) keyChar = String.fromCharCode(window.event.keyCode); else if (e) keyChar = String.fromCharCode(e.which); else return true; var number = parseFloat(val + keyChar); if (number != val + keyChar) return false; else return true; } </script> </head> <body> <input name="number" onkeypress="return restrict(this.value, event)"> </body> </html>