Checking to see if an image URL exists (JavaScript)

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August 27th, 2004, 06:47 PM

meatwad

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Join Date: May 2004

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Checking to see if an image URL exists (JavaScript)

Wondering if this is possible. I've seen a couple of topics on this forum relating to a similar process checking for website URLs, I just thought this might be different enough to warrant a new approach.

Here's my code:

Code:

<script>

function validate()
{
x=document.myForm
mov=x.myInput.value
scene=x.myOptions.value

 if (scene=="blank")
  {
   document.forms[0].reset();
   document.forms[0].elements[0].blur();
   return;
  }

 if (mov=="blank")
  {
   document.forms[0].reset();
   document.forms[0].elements[0].blur();
   return;
  }

 document.getElementById('imag').src=x.myOptions.value + x.myInput.value

}

</script>


<form name="myForm">

Search for Images :: 
	<select name="myInput" size="1">

            <option selected value="blank">-- Movie Index --</option>
	    <option value="_Mov_1.JPG">First Movie
	    <option value="_Mov_2.JPG">Second Movie
	    <option value="_Mov_3.JPG">Third Movie
	    <option value="_Mov_4.JPG">Fourth Movie

	</select> 

	<select name="myOptions" size="1" onchange="validate()">

            <option selected value="blank">-- Scene Index --</option>
	    <option value="Scene_One">Scene One
	    <option value="Scene_Two">Scene Two
	    <option value="Scene_Three">Scene Three
	    <option value="Scene_Four">Scene Four
	    <option value="Scene_Five">Scene Five
	    <option value="Scene_Six">Scene Six
	    <option value="Scene_Seven">Scene Seven

	</select> 
</form>

<img id="imag" src="splash.JPG">

What I want to do is check and see if there is actually an image called, for example, "Scene_One_Mov_1", and if there isn't redirect the user to an error message. Would probably be written in an "if ... else" statement.

Thank you for your time

Meatwad

August 27th, 2004, 06:52 PM

obi_wonton

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Join Date: Apr 2004

Location: Toronto, CANADA

Posts: 598

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Hmm... sorry, not about to go through all that mess. Here's one way to get it done:

Code:

<img src='invalid_url.png' onerror="alert('image does not exist/you are not connected to the internet');"

If you were to use a form to gather the urls to check, and then use a function to change the url of a 1x1 pixel image. If there was a problem, the onerror event would be triggered, and you can execute whatever code you want.

__________________
May the source be with you - obi_wonton

Last edited by obi_wonton : August 27th, 2004 at 06:54 PM.

August 27th, 2004, 08:10 PM

meatwad

Contributing User

Join Date: May 2004

Location: who wants to know?

Posts: 32

Time spent in forums: 1 h 10 m 36 sec
Reputation Power: 9

shweet.

Quote:

Originally Posted by obi_wonton

Hmm... sorry, not about to go through all that mess. Here's one way to get it done:

Code:

<img src='invalid_url.png' onerror="alert('image does not exist/you are not connected to the internet');"

Perfect fit! Thank you.

Checking to see if an image URL exists (JavaScript)

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