Redirect does not work, I don’t know why, below is the brief code:
public function actionUpdate($id)
{
Yii::app()->language = 'zh_cn';
$model=$this->loadModel($id);
if(isset($_POST['DYClass'])) {
$model->save();
$this->redirect(array('schedule')); // it didn't redirect after save
}
$this->render('update',array(
'model'=>$model,
));
}
Are you sure that isset($_POST[‘DYClass’]) is true?
If yes, then what exactly happens after submit?
Yes, I am sure that isset($_POST[‘DYClass’]) is true, because I tried replacing the redirect code with just “return”, it will return to a blank page.
After submit, it stayed on the update page, didn’t redirect to any other page and didn’t show any error.
The more weird thing is that if I replace the redirect code with echo and return as below, it didn’t return to a blank page with “ok” text either, just stayed on the update page.
public function actionUpdate($id)
{
Yii::app()->language = 'zh_cn';
$model=$this->loadModel($id);
if(isset($_POST['DYClass'])) {
$model->save();
echo "ok";
return;
}
$this->render('update',array(
'model'=>$model,
));
}
Niiiiiiice.
Ok, is it just a plain (I mean non-ajax) request?
Can you check what headers are being sent on response? (you can do it for example in google chrome dev console, or firebug)
I used chrome console, wow, how great it is, I never knew that I can use it to debug.
Actually, I am not familiar with ajax. 
what the error showed in the chrome console when I click the submit button is as below:
[b]Uncaught TypeError: Object #<Object> has no method ‘sendMessage’ Browser.js:2
Browser.sendToExtension Browser.js:2
g init.js:2
(anonymous function) init.js:4
Uncaught ReferenceError: xl_chrome_menu is not defined xl.js:111
HideXLMenu xl.js:111
onDocClick[/b]
Are you familiar with these errors?
Thanks. 
Oh, that’s nothing, seems like some browser extension is broken.
Then how should I debug it? Thanks.
You can use console to investigate request/response headers, ajax requests and so on.
But first try to turn off ajax and client validation of your form.
I resolved it. haha ~~
I enabled “validateOnSubmit” in form, but in action, I didn’t add validation code:
if(isset($_POST['ajax']) && $_POST['ajax']==='dyclass-form'){
echo CActiveForm::validate($model);
Yii::app()->end();
}
Thanks for your help.