call alert in php

[mingwww]

Hi:

I have a php script that runing to check some form input. after I got some error input found, the script(php) should prompt a error message just like the java script alert. this php script should not produce any html file.

How can I do that ?

thanks a lot !!!

[sarahk]

I think you need to do some reading about the diff between client side (javascript) and serverside (php, asp, java) processing.

When you submit a form to php the whole form goes and you will be left with a blank screen if you don't output something.

You have choices, basically output the whole form again with a error message in the html or at the very end have

if (isset($errormsg))
  echo "<script language='javascript'>\n alert('$errormsg');\n </script>";

[KoshNaranek]

Use JavaScript 🙂

<script language="javascript">
<!--
function check(theform) {
if (theform.user.value=="") {
alert("Enter Username!");
return false; }
if (theform.pwd.value=="") {
alert("Enter a password!");
return false; }
else { return true; }
}
//-->
</script>

<TABLE CLASS=border WIDTH="100%" ALIGN="CENTER" BORDER="0" cellpadding=3 cellspacing=3>
<tr><Th ALIGN="CENTER"><font size=3><b><?=MSG_TI_LOGIN?></b></th></TR>
<TR><TD CLASS=back ALIGN="CENTER"><br>
<form action="index.php" method="post" name='login' onsubmit="return check(this);">
Username:</br><input type="text" name="user" size="11"><br>
<br>
PASSWORD:</br><input type="password" name="pwd" size="11"><br>
<br>
</td></td>
<tr><td align=center>
<input type="hidden" name="login" value="LOGIN"><br>
<input type="submit" value="<?=MSG_BT_LOGIN?>">
</form>
<!set the focus to the field "username">
<script type="text/javascript">document.login.user.focus()</script>

[intenz]

A function would be a good idea...

function alert($msg = '')
{
     if(!$msg) $msg = 'Go sit in a corner' . "\n";
     echo '<script language="JavaScript">' . "\n" . 'alert("$msg");' . "\n" . '</script>';
}

Then you call it with e.g. alert(); or alert('Alert message here');

[bastien]

if ((!$newpassword)&&(!newpassconfim)){
//update all other info - leave old password alone
}elseif ($newpassword!=$newpassconfim){
//error check to see if passwords match- if they don't send error
//message and the user back to the form. note that passwords
//do not persist in the browser forms...you may want to code
//to remember all the other values (if any) to allow for best
//user interface and least aggravation.

//this script creates a pop up warning box and when clicked
//will take the user back one page. or you can handle it
//another way, it's all good.

echo "html><script language=\"javascript\">
function errors(){
alert("The new passwords do not match!");
history.go(-1);
}
</script></html>";
}elseif ($newpassword==$newpassconfim){
//update the data changes including the password
}