PHP same page echoing (using die funct.)
<?php //filename signup.php
ob_start();
include('dat.php');
if (!empty($_POST)){
if ($pass!="d41d8cd98f00b204e9800998ecf8427e" OR $user!="") { // 1
$result=mysql_query($sql);
if(mysql_error()) {
die('Sorry, this username already exists'); // 2
}
} else {
echo "Please enter the Password";
}
}
ob_end_flush();
?>
<html>
<body>
<f开发者_C百科orm name="form1" method="post" action="signup.php"> <!--3-->
Username<input name="myusername" type="text" id="myusername" />
Password<input name="mypassword" type="text" id="mypassword" />
e-mail<input name="email" type="text" id="email" />
<input type="submit" name="Submit" value="Login" />
</form>
</body>
</html>
This is a sign up page (All the mysql details are missing here, they are included in dat.php) . If there is ny error , it is displayed in the same page.
problem 1 : [ //1 ] what is the operator for OR , in this case I have used the condition for if the pass or user is blank,but the OR is not working neither || , used in javascript. problem 2 : [ //2 ] if die is used , then the statement is printed in the new window , but I want it to appear in the same window...I also used echo, it worked but I feel like i am missing the main function of 'die' by using 'echo'. problem 3 : [<!--3--> ] how can I replace signup.php as action to something like SERVER_PAGE or whatever... ORis the same as||except thatORhas a lower precedence than||. This can cause logical errors when it’s used with other operators with a higher precedence thanORbut a lower precedence than||like the assignment operators:$var = false OR true; // ($var = false) OR true; var_dump($var); // bool(false) $var = false || true; // $var = (false || true); var_dump($var); // bool(true)So I recommend you to rather use
||thanOR.diedoes print the passed string and quits the execution of the current script. Personally, I wouldn’t use usediebut implement a more decent error handling like storing the error message in a variable and print it in the document like this:$errors = array(); if (!empty($_POST)) { if ($pass!="d41d8cd98f00b204e9800998ecf8427e" || $user!="") { $result=mysql_query($sql); if (mysql_error()) { $errors[] = 'Sorry, this username already exists'; } } else { $errors[] = "Please enter the Password"; } } if (!empty($errors)) { echo 'There were some errors:'; echo '<ul><li>', implode('</li><li>', $errors), '</li></ul>'; }If you use an empty URL for the
actionattribute, it refers to the very same URL:<form name="form1" method="post" action="">
Some further tips:
- Use
$_SERVER['REQUEST_METHOD'] === 'POST'to test the request method instead of testing!empty($_POST). - Avoid register globals. So use
$_POST['pass']instead of$passif you want to refer to the parameter pass passed by POST.
Use the following form tag POST to the same script... that way if you rename the file it'll continue to work.
<form name="form1" method="post" action="<?php echo $_SERVER['PHP_SELF'] ?>">
problem 1: || (pipe pipe is OR)
problem 2: die stops dead right where it was called. Find a way to return false to the other script and die there.
problem 3: Not sure what you want here.
It is a logical operator. The same as
||but with lower precedence.
What do you mean by but the OR is not working neither || ? Do you get an exception? What should the result be? The syntax seems to be correct.
Maybe you are using a wrong logical expression. What should it do? Currently it evaluates totrue, if$passis notd41d8cd98f00b204e9800998ecf8427eor if the$useris not empty.Read about
die()in the manual, it is the same asexit():Output a message and terminate the current script
It is perfectly valid to just use
echohere, because you want that the script continues executing.What do you mean? Something like:
<?php define('SERVER_PAGE', 'signup.php'); ?> // later <form name="form1" method="post" action="<?php echo SERVER_PAGE ?>">?
first one and Second one: As told by Gumbo
Answer for the third one:
3.<form name="form1" method="post" action="<?php echo $_SERVER['PHP_SELF'] ?>">
@Mikey1980 : thanks!
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