Detecting ActiveRecord variable changes?

Yii 1.1 General Discussion
1

Just curious to see if there is an alternative way for detecting to see if the user has changed the values in a model before it saves.

Currently right before the $model->save() happens, I have a block of code that goes out to the database and grabs the same record to do a before and after comparison.


        $criteria = new CDbCriteria;

        $criteria->condition='id=:id';

        $criteria->params=array(':id'=>$model->id);

      	$oldModel = entry::model()->find($criteria);


      	if($model->save())

      	{

      	  $model->determineState($oldModel); // where we determine if anything changed

      	  $this->redirect(array('view','id'=>$model->id));

      	}
2

Assuming the model is derived from CActiveRecord:

CActiveRecord has a property tableSchema which is of type CDbTableSchema.

In CDbTableSchema is a property columnNames.

Add a private property $_dataChanged to your model which is set to true (in __set()) when a value changes.

Override the magic method __set():




public funcion __set($prop)

{

  if(in_array($prop,$this->tableSchema->columnNames)){

    $this->_dataChanged=true;

  }

  parent::__set($prop);

}

To reset the $_dataChanged property:




public function afterSave()

{

  $this->_dataDhanged=false;

}
3

I need to look for specific variables that have changed, but I think this will work perfectly. Thanks for your help.

4

you can record the old values on afterFind(),

and add determineState() function in your model, compare and get the result~

5

I could also do this, thanks. :lol:

6

Thanks for your answer! It works for me too.

But take a look to the magic method __set specification:

Without second parameter $value I get the PHP error.




public void __set ( string $name , mixed $value )