Safe "Submit" Button

Introduction

When a user on web form presses "Submit" button for sending data to web server, then the web server runs a script, query, etc. This may take uncertain time up to 1 minute. But the user sees a static page and may think: "I did not press the button or something is wrong" and press the button again many times. So the web server may get many HTML queries. This will increase CPU usage on the server and may return incorrect results.

Background

The idea is simple.

• Step 0 (may skip): Check the form: run function "OnSubmit" in tag FORM, check tag INPUT ("required" and "pattern" attributes).
• Step 1: Change text on the button to "Please wait...".
• Step 2: Disable the button.
• Step 3: Send query.

Using the Code

Just add code to input tag:

    <input type="submit" name="Submit" value="Submit"  
önclick = "this.form.check(); this.value='Please wait...'; this.disabled=true; this.form.submit();" />    

So see 'on click' event.

Step 0. Check the Form

 this.form.check(); 

Step 1. Change Text on the Button

 this.value='Please wait...';    

Step 2. Disable the Button

 this.disabled=true;    

Step 3. Press the Button Programmatically

 this.form.submit();    

Points of Interest

See also:

• HTML Forms and Input
• Submit Object
• onclick Event
• Form submit() method

History

• 1.1 | Added Step 0: Check form | 06.05.2013