The `onblur` event in Javascript is triggered when the element loses focus.

The `onkeydown` occurs on an element that has the focus when a key is pressed down and occurs periodically until the key is released.

If I want to validate a date field, the `onkeydown` event concerns 9 and 13 (`enter` and `tab` key).
But when I press the enter key, then I receive duplicate alert message.
Of course in this case we have two tests, `onblur` and `onkeydown` event.

this is the html code :

```
<html:text      onblur="return onDateChange(this);"
        onkeydown="return onDateKeyPress(this);"/>

```

the onDateChange() method is :

```
function onDateChange(obj){
//validateField is an externatl javascript method which trigger an alert message if we have errors in date 
        if(validateField(obj,'date',dateFormat)){
        //do instructions
        }
}

```

and finally the `onDateKeyPress()` method is :

```
function onDateKeyPress(obj){
    if(window.event.keyCode == 9)
    {  
       if(validateField(obj,'date',dateFormat))
       {
           //do instructions
       }
    }
    if(window.event.keyCode == 13)
    {  
      if(validateField(obj,'date',dateFormat))
      { 
        //do instructions
      }
    }
}

```

So, the problem is to have **one** display alert message.
Any suggestions?