Solved

how can i know if a photo is available  or not before puting it?

Posted on 2008-10-14
8
170 Views
Last Modified: 2009-07-29
i have 30 photo links that some of them dont work the photo is not there so when i try to see it like this

  <img src="<?php echo $photo[$p];?>"/></br>
i get a x on the photo like its unavailable

so how can i know that its unavailable before and not showing it?
0
Comment
Question by:mgtm3
  • 3
  • 3
  • 2
8 Comments
 
LVL 24

Accepted Solution

by:
glcummins earned 350 total points
Comment Utility
You can use get_headers() to determine if a URL returns a valid response before using it:

<?php
 

list($response_code) = get_headers($photo[$p]);
 

if (stristr($response_code, '200 OK'))

{

   // The photo exists

   echo $photo[$p];

}

else

{

   // Take whatever action is necessary, like outputting a placeholder image URL.

}

?>

Open in new window

0
 

Author Comment

by:mgtm3
Comment Utility
is there any faster code?
0
 
LVL 39

Assisted Solution

by:Roger Baklund
Roger Baklund earned 150 total points
Comment Utility
If the images are on the local server, you can use file_exists().

You can use a placeholder image, like glcummins suggests, or remove the image completely, i.e. only display the image element if the image actually exists:
<?php if(file_exists($photo[$p]))

  echo '<img src="'.$photo[$p].'"/></br>';

?>

Open in new window

0
 

Author Comment

by:mgtm3
Comment Utility
but the image is not on the sever and the command that glucummis takes for ever
0
How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

 
LVL 39

Expert Comment

by:Roger Baklund
Comment Utility
It's probably the network and/or the remote server that is slowing you down. There is no way around this. Some packets have to travel across the network to determine if the file exists, and the remote server will use some time to respond. You should of course remove links to non-existing photos from your page, that would solve the problem.
0
 

Author Comment

by:mgtm3
Comment Utility
how can i remove the links? you mean not showing the image
0
 
LVL 39

Expert Comment

by:Roger Baklund
Comment Utility
With links I meant "photo links" or image URLs. How did they get into $photo[$p] ? They are probably read from some database table? You should delete or otherwise 'block' these records from that table.
0
 
LVL 24

Expert Comment

by:glcummins
Comment Utility
I run a large server with many millions of image references to other servers. I run a process in the background that periodically checks for the existence of those images, and updated a database record if they do not exist.

When the customer loads the website, my front-end scripts instantly know if the remote image is available, and do not need to run the slow get_headers() command in real-time.

Perhaps a similar system will work for you?
0

Featured Post

6 Surprising Benefits of Threat Intelligence

All sorts of threat intelligence is available on the web. Intelligence you can learn from, and use to anticipate and prepare for future attacks.

Join & Write a Comment

Introduction HTML checkboxes provide the perfect way for a web developer to receive client input when the client's options might be none, one or many.  But the PHP code for processing the checkboxes can be confusing at first.  What if a checkbox is…
Nothing in an HTTP request can be trusted, including HTTP headers and form data.  A form token is a tool that can be used to guard against request forgeries (CSRF).  This article shows an improved approach to form tokens, making it more difficult to…
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
The viewer will learn how to create a basic form using some HTML5 and PHP for later processing. Set up your basic HTML file. Open your form tag and set the method and action attributes.: (CODE) Set up your first few inputs one for the name and …

771 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now