Graphics and Classes

ecg

I've learnt how to use classes.
I've learnt how to use the graphics (bargraphs etc).
Now to put them together. I think I'm missing something easy.. but here goes:
I have a file called graphclass.php which has my class graph. I also have a file called trial1.php which includes graphclass.php.
class graph includes two functions:
bargraph() and piegraph().
Problem 1) the Header tag

header("Content-Type: image/png");

can only be defined once. so if I try to call bargraph() and piegraph() from the same file it sees the Header defined twice.
Problem 2) Unless I use

ImagePNG($im, "test.png");

in graphclass.php and <IMG SRC = "test.png" Border = 0 > in trial1.php I can't display the graphs...

Any ideas?
Thanks :-)

Jona

[font=arial]I could be wrong, but if I do believe that when you use the content-type: image/png header, the data sent to the client becomes binary; thus, no HTML can be displayed. What I would do, is create the image on the server with PHP, and use the content-type: text/html header to display the image in HTML on a page. Then, simply overwrite the image each time the function is run.[/font]

[J]ona

ecg

Sorry. Think I must need more coffee or something.
I'm transposing a function that already existed into a class.
It used to be bargraph.php and piegraph.php and they were called from an asp (gasp shudder I know) page using:
<img src=<% = Application("WebAddress") & "/piegraph.php?s=" & rsdata.fields("x") %>>
And it worked fine without saving as "test.png".

So now I've lost myself in the layers.
I have trial1.php which includes graphclass.php and eventually I want to use trial1.php to process some data before calling the piegraph function so I'll need to call it from another file...

Can I just whimper now?

Jona

[font=arial]Couldn't you reproduce the ASP effect with PHP with something like this?[/font]

<img src="<?PHP echo("piegraph.php?s=".$_POST['x']);?>" border="0">

[J]ona

ecg

Hi. Thanks for the reply.
I don't need to use php for the call line...
currently I have call.html which
uses:
<table cellpadding="2" cellspacing="1" border="0" align="center">
<tr>
<td colspan=3 align=center>
<IMG SRC = "trial1.php?x=5" Border = 0 >
</td>
</tr>
</table>
to call the relevant php file. Which then uses graphclass to display the graphs.
I no longer have to use the 'save at file' option to display but I have no idea why...

Jona

Originally posted by ecg
I no longer have to use the 'save at file' option to display but I have no idea why...

[font=arial]This is because the image is dynamically generated, and not saved as a seperate file to the server. I've created an image creation PHP script which allows a user to type in text and colors for the text and background, and generate an image. I'm assuming you're using similar code. If I may point to the documentation: http://php.net/image [/font]

[J]ona

Mordecai

ImagePNG outputs no header. You'll have to manually output the header, and you should do this in trial1.php.
So, trial1.php will look something like this:

include("graphclass.php");
header("Content-type: Image/PNG");
//stuff to make graphs output

You could also use the <img> tag, if you wanted to, but it would require more work.