JavaScript onkeypress event
This section illustrates you the use of onkeypress event in JavaScript.
In the given example, we are going to show you how to restrict the user to enter any number into the input field. For this purpose, we have created a text field. On pressing the key to write the text on the textbox, you will see that it will take only characters, not the numbers. This is possible by using the onkeypress event. It occurs when a keyboard key is pressed or held down.
Here is the code:
<html> <h2>Textbox showing onkeypress event</h2> <script type="text/javascript"> function valid(e){ var num; var chars; var check; if(window.event){ num = e.keyCode; } else if(e.which){ num = e.which; } chars = String.fromCharCode(num); check = /\d/; return !check.test(chars); } </script> Enter text: <input type="text" onkeypress="return valid(event)"/> </html> |
On pressing the key, only characters get inserted in the text field: