Form validation using if array key exists

Question

Here is the html and Php code i have used:

<?php 
 require_once('include_function.php');
 require_once('validation_functions.php');
 $errors = array();
 $message ="";
 if(isset($_POST['submit'])){
    $username = trim($_POST['username']);
    $password = trim($_POST['password']);
    if (array_key_exists('submit', $_POST)){
    }
    $fields_required = array("username","password");
    foreach($fields_required as $field){
        $value = trim($_POST[$field]);
        if(!has_presence($value)){
            $errors[$field]= ucfirst($field). " Cant Be blank";
        }
    }
 }
?>
<!doctype html>
<html>
<head>
<meta charset="utf-8">
 <title>Single page Submission</title>
</head>
<body>
    <?php echo $message;?>
    <?php echo form_error($errors)?>
    <form action="form_with_validation.php" method="post">
        Username<input type="text" name="username" value=""/><br/>
        Password<input type="password" value="" name="password" /><br/>
        <input type="submit" name="submit" value="Submit" />
    </form>
</body>
</html>

And these are functions I have used

function has_presence($value){
    return isset($value) && $value !=="";
}
function form_error($errors=array()){
    $output = "";
    if(!empty($errors)){
        $output .="<div class=\"error\">";
        $output .="Please fix the following errors";
        $output .="<ul>";
        foreach($errors as $key => $field){
            $output .= "<li>{$field}</li>";
        }
        $output .="</ul>";
        $output .="</div>";
    }
    return $output;

}

Can someone please guide me to validate the form using if array key exists So that I get error message next to Or below the input field or any other method which does the needful

Jevgenijs Vaikulis · Accepted Answer · 2014-10-11 06:37:16Z

1

<?php 
    $errors = array();
    $message ="";
    if(isset($_POST['submited'])){
        $fields_required = array("username","password");
        foreach($fields_required as $field)
            if (!isset($_POST[$field]) || $_POST[$field]=="")
                $errors[$field]= $field. " Cant Be blank";
    }

    function form_error($errors=array()){ 
        $output = "";
        if(!empty($errors)) {
            $output .="<div class=\"error\">";
            $output .="Please fix the following errors";
            $output .="<ul>";
            foreach($errors as $key => $field){
                $output .= "<li>{$field}</li>";
            }
            $output .="</ul>";
            $output .="</div>";
        }
        return $output;
    }
}  
?>
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Single page Submission</title>
</head>

<body>
<?php echo $message;?>
<form action="form_with_validation.php" method="post">
<input type="hidden" name="submited" value="1" />
Username<input type="text" name="username" value=""/><br/>
Password<input type="password" value="" name="password" /><br/>
<input type="submit" name="submit" value="Submit" />
</form>
<?php echo form_error($errors)?>
</body>
</html>

edited Oct 11, 2014 at 6:37

answered Oct 11, 2014 at 6:27

Jevgenijs Vaikulis

6864 silver badges7 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

user4094161 Over a year ago

@evgenijs Vaikulis. I guess he wanted to print the error message next to or below the input fields separately. And you have done right but you have printed the error message all at once on the top.

sandeep S K Over a year ago

yes want print below the input field ,how can i do that?

Jevgenijs Vaikulis Over a year ago

ive changed script a bit. Errors must be shown right after your form.

sandeep S K Over a year ago

I am still getting the errors above the form,and i have asked for array exists key so that i can find out the key and print my error wherever i want

user4094161 · Accepted Answer · 2014-10-11 06:45:56Z

@sandeep S K Can you please try once below code? :

Note: Please include your required DB connection or validation files on the top of the script.

 <?php 
    function has_presence($value){
        return isset($value) && $value !=="";
    }
    function form_error($errors=array()){
        $output = "";
        if(!empty($errors)){
            $output .="<div class=\"error\">";
            $output .="Please fix the following errors";
            $output .="<ul>";
            foreach($errors as $key => $field){
                $output .= "<li>{$field}</li>";
            }
            $output .="</ul>";
            $output .="</div>";
        }
        return $output;

    }

     $errors = array();
     $message ="";
     if(isset($_POST['submit'])){
        $username = trim($_POST['username']);
        $password = trim($_POST['password']);
        if (array_key_exists('submit', $_POST)){
        }
        $fields_required = array("username","password");
        foreach($fields_required as $field){
            $value = trim($_POST[$field]);
            if(!has_presence($value)){
                $errors[$field]= ucfirst($field). " Cant Be blank";
            }
        }
     }
    ?>
    <!doctype html>
    <html>
    <head>
    <meta charset="utf-8">
     <title>Single page Submission</title>
    </head>
    <body>
        <?php echo $message;?>
        <?php  if(!empty($errors)) { ?>

                <div class="has_errors"> 
                    <ul>
                        <li>    
                            There are errors in your input. Please fix them and try again.
                        </li>
                    </ul>
                </div>
            <?php
        }
        ?>
        <form action="index.php" method="post">
            Username<input type="text" name="username" value=""/>
            <?php 
                if (array_key_exists('username', $errors)) {
                    ?>
                    <div class="has_errors"> 
                        <ul>
                            <li>    
                                <?php print $errors['username'];?>
                            </li>
                        </ul>
                    </div>
                    <?php
                }
            ?>
            <br/>
            Password<input type="password" value="" name="password" />
             <?php 
                if (array_key_exists('password', $errors)) { ?>
                    <div class="has_errors"> 
                        <ul>
                            <li>    
                                <?php print $errors['password'];?>
                            </li>
                        </ul>
                    </div>
                    <?php
                }
            ?>
            <br/>
            <input type="submit" name="submit" value="Submit" />
        </form>
    </body>
    </html>

Collectives™ on Stack Overflow

Form validation using if array key exists

2 Answers 2

4 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related