How to do I use Addrule() or ValidateRule() to create a custom rule for validation purposes.

peregrine

how would one use the AddRule() or ValidateRule() - a bit confusing for me.

e.g. to create a custom rule that checked to see if an integer was greater than 50.

there is currently a length rule - with a maximum in class.validation.php

A bit hard for me to decipher the function.

Todd

Yeah this isn't super easy. Let me explain the best I can.

First you have to call Gdn_Validation->AddRule() to make the rule available to the model. You usually do this in your model, but you can also do it in the controller. Just do it before saving.

// Call this inside your Gdn_Model class.
$this->Validation->AddRule('MyCustomRule', 'function:ValidateMyCustomRule');

// MyCustomRule: This is a name for the rule. It'll be used to generate error messages so you'll want to translate it too.
// ValidateMyCustomRule: You need to write this function. It will be passed the value to validate.

function ValidateMyCustomRule($Value) {
  if ($Value == 'peregrine rocks!')
    return TRUE;
  else
    return FALSE;
}

Now you can use your custom rule on any number of columns by calling Gdn_Validation->ApplyRule().

$this->Validation->ApplyRule('Description', 'MyCustomRule');

This readies the rule for validation, but doesn't actually validate the data yet. It just makes your model ready for validation. To validate you usually do something like this:

if ($this->Validate($Post, $Insert)) {
   $this->Save($Post);
}

So that's that and is really meant for formal model writing. Sometimes you just want to quickly validate some data in a plugin or a controller method. For this you can call the static method Gdn_Validation::ValidateRule().

$Valid = Gdn_ValidateRule($Post['Description'], 'Description', 'function:ValidateMyCustomRule', 'Incorrect!!!');
if ($Valid !== TRUE)
  $this->Form->AddError($Valid);

Really though, you just want to call Gdn_Form's ValidateRule.

$this->Form->ValidateRule('Description', 'function:ValidateRequired');
$this->Form->ValidateRule('Description', 'function:ValidateMyCustomRule', 'Incorrect!!!');
// Bunch of other rules.

if ($this->Form->ErrorCount() == 0) {
   // Redirect to a success page maybe.
}
// Otherwise just render the form and the errors will be displayed when you call echo $this->Form->Errors();

peregrine

thanks much Todd. I'll try to digest this.

422

if ($this->Form->ErrorCount() == 0) {

Doesnt this mean if error count does not equal zero ? So if it isnt zero then its got an error, so you wouldnt direct to success page?

Im pretty crap on php / js operators

peregrine

$this->Form->ErrorCount()   returns an error count

so if the returned error count is equal to 0

0 - one  would assume means no error count - meaning success

therefore 

($this->Form->ErrorCount() == 0)   would equate to True

if true
  then success

422

Gottya