why alert() not execute if I use before header()??

[iskhan]

if a JS's alert() use before header() use in a function like this:

e.g.

function goto_page()
{
        if(.............)
          {
           <? alert("Error:............"); <?php
           header("abc.php");
           }
}

alert not execute. why?

[trq]

If your example is anything to go by, its likely because its not within a js script block.

[iskhan]

It is obvious that every JS code is in the <script> </script> tags.

I give you a sample code If I forgot to mention JS tag it mean tags are there. so now what is the solution?

[Daniel0]

The solution to what? What are you looking to accomplish?

[Mchl]

Why is there <? before alert()? It's breaking JS probably.

[iskhan]

when I use the these two function in my function the alert dialog box not display and header() execute and program transfer to new page.

but I need first alert message display when I click OK then header() execute and program transfer to new page.

[anups]

function goto_page()
{
        if(.............)
          {
           <? alert("Error:............"); <?php
           header("abc.php");
           }
}

 

Javascript is executed at client side i.e in browser. 

 

But in above case you are redirecting the page to another location through PHP before sending o/p to the browser,

If browser is not getting any data it won't interpret it.

 

so u can use javascript to redirect the page 

 

alert('Error:---')
like location.href = 'abc.php';

[phpchamps]

Try this...

 

<?php
function goto_page()
{
        if(true){
		?>
		<script language="JavaScript1.2" type="text/javascript">
			alert("Error");
		</script>
		<?php
           header("http://www.google.com");
           }
}

goto_page();
?>

[Daniel0]

1) "If true"... seriously? True is always true, by definition.

2) You cannot send a header after you've started sending the response body.

[phpchamps]

yaa if true.. because i dont know which condition he is using.. i always want my condition to be true.. its just an example.... he can replace it by his own condition.....

 

The only problem he is facing that he want to display an alert box.......and then he want user to be redirected to specific page....

 

So, my code solves the prob...4 him....

[Daniel0]

So, my code solves the prob...4 him....

 

No it doesn't. You cannot send a header after you start sending the body like you do in your script. What he is trying to do is not possible.

[phpchamps]

as your requirement is only to redirect user. use javascript redirection.. use below code .

 

<?php
function goto_page()
{
        if(true){
		?>
		<script language="JavaScript1.2" type="text/javascript">
			alert("Error");
			window.location = "http://www.google.com";
		</script>
		<?php
        
           }
}

goto_page();
?>

[iskhan]

Is there any equivalent of JS's alert() function in PHP?If not it means that window.location = "http://.....";is the only solution.

[Mchl]

No there is not. PHP does not run in browser.