未定义的变量：在表单提交的文本字段中保存用户输入的数据

Question

When error_reporting(E_ALL); is turned on I'm having the following example of notice

Notice:  Undefined variable: name in /home/user/public_html/directory/subdirectory/test.php on line 111
Notice:  Undefined variable: identity in /home/user/public_html/directory/subdirectory/test.php on line 116

in every form field if I want to save user inputted data in text fields using session after the form is submitted by the users.

Example of my current code is as following:

GetSQLValueString($_POST['name'], "text"),
GetSQLValueString($_POST['identity'], "text")

  <?php  $_SESSION['form'] = $_POST; ?>

  <form action="<?php echo $editFormAction; ?>" method="post" name="userform" id="userform">
  <input name="name" type="text" id="name" value="<php$_SESSION['form']['name'] = '';?><php $_SESSION['form']['name']; ?>" size="25" />
  <input name="identity" type="text" id="identity" value="<php$_SESSION['form']['identity'] = '';?><php $_SESSION['form']['identity']; ?>" size="25" />

and so on.............

I gout suggestion about eliminating undefined index using

<php$_SESSION['form']['name'] = '';?>

as value of text field like,

 <input name="name" type="text" id="name" value="<php$_SESSION['form']['name'] = '';?><php $_SESSION['form']['name']; ?>" size="25" />

The above code resolves undefined index notice but produces undefined variable notice.

The form works well when error reporting is off.

Any idea, how to define the undefined variable in this case?

Answer 1

This notice is raised because before the form is posted, there are no values in $_SESSION['form'] but you try to display them. You can fix this by checking for a post and filling $_SESSION['form'] with an empty array if not:

if($_POST){
    $_SESSION['form'] = $_POST; 
}else{
    $_SESSION['form'] = array('name'=>'','identity'=>'' //etc);

}

?>


  <form action="<?php echo $editFormAction; ?>" method="post" name="userform" id="userform">
  <input name="name" type="text" id="name" value="<?php echo $_SESSION['form']['name'] ;?>" size="25" />
  <input name="identity" type="text" id="identity" value="<?php echo $_SESSION['form']['identity'];?>" size="25" />

Alternately you could use isset before echoing each variable.

Also note that you must use echo or print to actually display the values.