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Difference between revisions of "Client-side form validation"

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[[Category:Development]]
+
==Introduction==
 
+
== Intro ==
+
 
+
 
Joomla 1.5 contains a behavior '''JHTMLBehavior::formvalidation()''' which enables the script '''validate.js'''.
 
Joomla 1.5 contains a behavior '''JHTMLBehavior::formvalidation()''' which enables the script '''validate.js'''.
It uses '''mootools''' (I think) and allows your form and its elements to be validated.   
+
It uses '''mootools''' and allows your form and its elements to be validated.   
  
 
'''Note:''' For more recent versions of Joomla (1.5.2) use '''JHTML::_('behavior.formvalidation')''' instead of '''JHTMLBehavior::formvalidation()'''
 
'''Note:''' For more recent versions of Joomla (1.5.2) use '''JHTML::_('behavior.formvalidation')''' instead of '''JHTMLBehavior::formvalidation()'''
  
== To enable the validation ==
+
==Enable the Validation==
The only thing you have to do is set the '''classes''' of the form and elements to specified meanings.
+
The only thing you have to do is set the '''classes''' of the form and elements to the specified meanings.
 
Classes:
 
Classes:
=== Form ===
+
===Form===
 
* form-validate -> enable validation
 
* form-validate -> enable validation
=== Form elements ===
+
===Form elements===
 
* required
 
* required
 
* validate-username
 
* validate-username
Line 20: Line 17:
 
* validate-email
 
* validate-email
 
* validate-[custom] -> custom handlers have to be set then!
 
* validate-[custom] -> custom handlers have to be set then!
== Style invalid elements ==
+
==Style Invalid Elements==
 
If some elements don't validate they will get the class
 
If some elements don't validate they will get the class
 
* invalid
 
* invalid
If you style this to e.g. red background and white foreground, your users will be able to see which fields are wrong.
+
If you style the class in the cascading style sheet, your users will be able to see which fields are wrong. For instance:
 
+
<source lang="css">
== Really only accept form after validation ==
+
.invalid {color:red;}
If you don't want the form to submit anything unless the values are validated, here's a nice script:<source lang="php">
+
</source>
 +
==Only Accept the Form After Validation==
 +
If you don't want the form to submit anything unless the values are validated, here's a nice script:
 +
<source lang="php">
 
<?php JHTMLBehavior::formvalidation(); ?>
 
<?php JHTMLBehavior::formvalidation(); ?>
 
<script language="javascript">
 
<script language="javascript">
 
function myValidate(f) {
 
function myValidate(f) {
if (document.formvalidator.isValid(f)) {
+
  if (document.formvalidator.isValid(f)) {
f.check.value='<?=JUtility::getToken()?>';//send token
+
      f.check.value='<?php echo JUtility::getToken(); ?>'; //send token
return true;  
+
      return true;  
}
+
  }
else {
+
  else {
alert('Some values are not acceptable.  Please retry.');
+
      var msg = 'Some values are not acceptable.  Please retry.';
}
+
 
return false;
+
      //Example on how to test specific fields
 +
      if($('email').hasClass('invalid')){msg += '\n\n\t* Invalid E-Mail Address';}
 +
 
 +
      alert(msg);
 +
  }
 +
  return false;
 
}
 
}
 
</script>
 
</script>
Line 43: Line 48:
 
<input type="hidden" name="check" value="post"/>
 
<input type="hidden" name="check" value="post"/>
 
...
 
...
<input type="text" name="email" size="30"  class="required validate-email"/>
+
<input type="text" name="email" id="email" size="30"  class="required validate-email"/>
 
...
 
...
 
<input type="submit" value="Submit" />
 
<input type="submit" value="Submit" />
 
</form></source>
 
</form></source>
  
The page that receives the value can check several things:<source lang="php">
+
The page that receives the value can check several things:
defined( '_JEXEC' ) or die( 'Restricted access' );  //Verify Joomla enabled
+
<source lang="php">
  
 +
defined( '_JEXEC' ) or die( 'Restricted access' );  //Verify Joomla enabled
 
$jAp=& JFactory::getApplication();
 
$jAp=& JFactory::getApplication();
 
if ($_POST['check']!=JUtility::getToken()) {
 
if ($_POST['check']!=JUtility::getToken()) {
//First verify if by a javascript error or other possibilities the form has not been submitted without the validation
+
  // First verify (by a Javascript error or other methods) that the form has not been submitted without the validation
if ($_POST['check']=='post') $jAp->enqueueMessage('Please check all the fields of the form, aub.<br/>
+
  if ($_POST['check']=='post') $jAp->enqueueMessage('Please check all the fields of the form, aub.<br/>
If your browser blocks javascript, then this form will never be succesfull. This is a security measure.','error');
+
If your browser blocks Javascript, then this form will never be successful. This is a security measure.','error');
//If then still the check isn't a valid token, do nothing as this might be a spoof attack or other invalid form submission
+
  // If the check still isn't a valid token, do nothing. This might be a spoof attack or other invalid form submission
return false;
+
  return false;
}</source>
+
}
 
+
</source>
== Custom handlers ==
+
==Custom Handlers==
If you want a custome handler, you can add one to the class, as follow example (defined AFTER the validate.js):<source lang="php">Window.onDomReady(function() {
+
If you want a custom handler, you can add one to the class, as in the following example (defined AFTER the validate.js):
document.formvalidator.setHandler('birth', function(value) {
+
<source lang="php">Window.onDomReady(function() {
regex=/^\d{4}(-\d{2}){2}$/;
+
  document.formvalidator.setHandler('birth', function(value) {
return regex.test(value);
+
      regex=/^\d{4}(-\d{2}){2}$/;
})
+
      return regex.test(value);
})</source>
+
  })
 +
})
 +
</source>
 
You can then set any class to validate-birth to make it validate as yyyy-mm-dd.  (Valid date is not checked!)
 
You can then set any class to validate-birth to make it validate as yyyy-mm-dd.  (Valid date is not checked!)
 +
 +
If you want a custom handler to check both the passwords (Password and Confirm Password) are same, please add the following script after the validate.js:
 +
<source lang="javascript">
 +
<script type="text/javascript">
 +
<!--
 +
window.addEvent('domready', function(){
 +
document.formvalidator.setHandler('passverify', function (value) { return ($('password').value == value);
 +
});
 +
});
 +
// -->
 +
</script>
 +
</source>
 +
Add add the class "validate-passverify" to the input field as below:
 +
<source lang="html4strict"><input class="inputbox required validate-passverify" type="password" id="password2" name="password2" size="40" value="" />
 +
</source>
 +
 +
==Work Around when Using with JToolBar==
 +
If you are using JHTML::_('behavior.formvalidation') with JToolBar, for example use in backend, the above method will not work. This is because it depends on onSubmit event which did not fire when we call form.submit via JavaScript. To work around this, we have to move the code in onSubmit to be in submitbutton function override. This will look like this:-
 +
<source lang="javascript">
 +
<script type="text/javascript">
 +
/* Override joomla.javascript, as form-validation not work with ToolBar */
 +
function submitbutton(pressbutton) {
 +
    if (pressbutton == 'cancel') {
 +
        submitform(pressbutton);
 +
    }else{
 +
        var f = document.adminForm;
 +
        if (document.formvalidator.isValid(f)) {
 +
            f.check.value='<?php echo JUtility::getToken(); ?>'; //send token
 +
            submitform(pressbutton);   
 +
        }
 +
        else {
 +
            var msg = new Array();
 +
            msg.push('Invalid input, please verify again!');
 +
            if ($('title').hasClass('invalid')) {
 +
                msg.push('<?php echo JText::_('COM_JONGMAN_ERROR_SCHEDULE_TITLE_IS_REQUIRED')?>');   
 +
            }
 +
            if($('admin_email').hasClass('invalid')){
 +
                msg.push('<?php echo JText::_('COM_JONGMAN_ERROR_INVALID_EMAIL')?>');
 +
            }
 +
            alert (msg.join('\n'));
 +
        }
 +
    }   
 +
}
 +
</script>
 +
</source>
 +
<noinclude>[[Category:Tutorials]][[Category:Development]][[Category:Component Development]]</noinclude>

Revision as of 05:04, 7 November 2012

Contents

Introduction

Joomla 1.5 contains a behavior JHTMLBehavior::formvalidation() which enables the script validate.js. It uses mootools and allows your form and its elements to be validated.

Note: For more recent versions of Joomla (1.5.2) use JHTML::_('behavior.formvalidation') instead of JHTMLBehavior::formvalidation()

Enable the Validation

The only thing you have to do is set the classes of the form and elements to the specified meanings. Classes:

Form

  • form-validate -> enable validation

Form elements

  • required
  • validate-username
  • validate-password
  • validate-numeric
  • validate-email
  • validate-[custom] -> custom handlers have to be set then!

Style Invalid Elements

If some elements don't validate they will get the class

  • invalid

If you style the class in the cascading style sheet, your users will be able to see which fields are wrong. For instance:

.invalid {color:red;}

Only Accept the Form After Validation

If you don't want the form to submit anything unless the values are validated, here's a nice script:

<?php JHTMLBehavior::formvalidation(); ?>
<script language="javascript">
function myValidate(f) {
   if (document.formvalidator.isValid(f)) {
      f.check.value='<?php echo JUtility::getToken(); ?>'; //send token
      return true; 
   }
   else {
      var msg = 'Some values are not acceptable.  Please retry.';
 
      //Example on how to test specific fields
      if($('email').hasClass('invalid')){msg += '\n\n\t* Invalid E-Mail Address';}
 
      alert(msg);
   }
   return false;
}
</script>
<form id="WV-form" method="post" class="form-validate" onSubmit="return myValidate(this);">
<input type="hidden" name="check" value="post"/>
...
<input type="text" name="email" id="email" size="30"  class="required validate-email"/>
...
<input type="submit" value="Submit" />
</form>

The page that receives the value can check several things:

defined( '_JEXEC' ) or die( 'Restricted access' );  //Verify Joomla enabled
$jAp=& JFactory::getApplication();
if ($_POST['check']!=JUtility::getToken()) {
   // First verify (by a Javascript error or other methods) that the form has not been submitted without the validation
   if ($_POST['check']=='post') $jAp->enqueueMessage('Please check all the fields of the form, aub.<br/>
If your browser blocks Javascript, then this form will never be successful. This is a security measure.','error');
   // If the check still isn't a valid token, do nothing. This might be a spoof attack or other invalid form submission
   return false;
}

Custom Handlers

If you want a custom handler, you can add one to the class, as in the following example (defined AFTER the validate.js):

Window.onDomReady(function() {
   document.formvalidator.setHandler('birth', function(value) {
      regex=/^\d{4}(-\d{2}){2}$/;
      return regex.test(value);
   })
})

You can then set any class to validate-birth to make it validate as yyyy-mm-dd. (Valid date is not checked!)

If you want a custom handler to check both the passwords (Password and Confirm Password) are same, please add the following script after the validate.js:

<script type="text/javascript">
<!--
        window.addEvent('domready', function(){
                document.formvalidator.setHandler('passverify', function (value) { return ($('password').value == value); 
                });
        });
// -->
</script>

Add add the class "validate-passverify" to the input field as below:

<input class="inputbox required validate-passverify" type="password" id="password2" name="password2" size="40" value="" />

Work Around when Using with JToolBar

If you are using JHTML::_('behavior.formvalidation') with JToolBar, for example use in backend, the above method will not work. This is because it depends on onSubmit event which did not fire when we call form.submit via JavaScript. To work around this, we have to move the code in onSubmit to be in submitbutton function override. This will look like this:-

<script type="text/javascript">
/* Override joomla.javascript, as form-validation not work with ToolBar */
function submitbutton(pressbutton) {
    if (pressbutton == 'cancel') {
        submitform(pressbutton);
    }else{
        var f = document.adminForm;
        if (document.formvalidator.isValid(f)) {
            f.check.value='<?php echo JUtility::getToken(); ?>'; //send token
            submitform(pressbutton);    
        }
        else {
            var msg = new Array();
            msg.push('Invalid input, please verify again!');
            if ($('title').hasClass('invalid')) {
                msg.push('<?php echo JText::_('COM_JONGMAN_ERROR_SCHEDULE_TITLE_IS_REQUIRED')?>');    
            }
            if($('admin_email').hasClass('invalid')){
                msg.push('<?php echo JText::_('COM_JONGMAN_ERROR_INVALID_EMAIL')?>');
            }
            alert (msg.join('\n'));
        }
    }    
}
</script>