How to validate a form using if statements

**Rabbit** · Apr 30 '13, 03:36 PM

I don't understand your question.

but the password is not submited

What password? What does that have to do with anything?

before submiting the data for any missing fields the user must be notified

I don't see anywhere in your code where you notify the user.

Also, the code logic doesn't make any sense. You're checking values before any of the values are populated. You've also either split your check from the insert code so they don't overlap or you have a phantom else. It's difficult to parse out your use of brackets.

**RodPhp5** · Apr 30 '13, 03:48 PM

When i say the password is not submited i mean, when i check the database for the data that i inserted using the form, everything is there except the password... I try to notify the user by using those if statements. Or if maybe you can just show me a sample logic on how i can validate my form before posting the data into the database.

**Rabbit** · Apr 30 '13, 04:03 PM

When i say the password is not submited i mean, when i check the database for the data that i inserted using the form, everything is there except the password...

Okay, but what does that have to do with the question? I don't understand the relevance.

I try to notify the user by using those if statements.

Except that I don't see any notification anywhere. All you're doing is populating variables but not doing anything with them.

Or if maybe you can just show me a sample logic on how i can validate my form before posting the data into the database.

Here's a quick example. It's off the top of my head so it may not be syntactically correct but the logic is there.

Code:

<?
if (isset($_POST['Submit'])) {
   $errormessage = '';
   $username = '';
   $username = $_POST['username'];

   if (strlen($username) > 50) {
      $errormessage = $errormessage . 'The username is longer than fifty characters. ';
   }

   if (strlen($errormessage) > 0) {
      echo $errormessage;
   } else {
      // insert into your database
   }
}
?>

**Sherin** · Jan 6 '21, 06:10 AM

Try This Code

Code:

 function checkExpire(form)
  {
    // regular expression to match required date format
    re = /^\d{1,2}\/\d{1,2}\/\d{4}$/;

if(form.txtExpire.value != '' && !form.txtExpire.value.match(re)) {
  alert("Invalid date format: " + form.txtExpire.value);
  form.txtExpire.focus();
  return false;
} 

return true;
  }

**williamryeager** · Jan 12 '21, 12:52 PM

**bakertaylor28** · Feb 25 '21, 02:24 AM

You don't need the "else" rather, only the "if".

Code:

<?php
If  ($username = foo) { 
echo 'username';
}
echo 'do something else';
?>

will return username if username = foo, and will return do something else if username = anything else. "else" or "elseif" is not required, unless there are three or more cases. The way if cases work is like this:

Code:

<?php
If (Case1) { 
echo 'Response to case 1';
} elseif (Case2) {
echo 'Response to Case2';
} else {
echo 'response to case 3, if BOTH case1 and case2 return false';
}
echo 'continue code here';
?>

BUT, we can also have:

Code:

<?php
if (Case1){
echo 'Response to Case1';}
echo 'Response to case 2 is the continuation of the code';
?>

Or we can have:

Code:

<?php
if (Case1) {
echo 'Response to Case1';
} elseif (Case2) { 
'Response to Case2';
}
echo 'continue the code';
?>

Finally we can have:

Code:

<?php
if (case1) {
echo 'response to case1';
} elseif {
echo 'response to case2;
} else {
if (Condition3) {
echo 'response to condition3';
} elseif (Condition4) {
echo 'response to condition4';
} else (Condition 5) {
echo 'response to condition 5'; 
}
}
echo 'continue script here';
?>

The limitation being that case2 must return false before the script will evaluate for conditions 3, 4, or 5.
The way we can make sure that the script exits after each case is to include the following as the last line of each case:

Code:

<?php
if (case1) {
echo 'case1 code here';
exit;
} elseif (case2) {
...
}
...
?>

Therefore, you would want to use something like:

Code:

  if($full_name_length >50) {
                echo 'error message here';
                exit;
  }
if ( !isset ($_POST['surname'] ) ) {
echo 'error message if user did not input a surname'; 
exit;
}

if (some other error condition) {
echo 'error message';
exit;
}
echo 'do code here if no errors';

How to validate a form using if statements

How to validate a form using if statements

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