swift2 Xcode7.0 Expected ',' separator [duplicate]

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• Divided operation in Swift 1 answer

if ( username.isEqualToString("")||
            useremail.isEqualToString("") ||userpassword.isEqualToString("")||
            userphonenumper.isEqualToString("")
            ){
            let alert = UIAlertController(title: "Sign Up Failed!", message:"Please enter your data", preferredStyle: .Alert)
            alert.addAction(UIAlertAction(title: ",ok", style: .Default) { _ in })
            self.presentViewController(alert, animated: true){}
        } 

I use Xcode7 and Swift2 when i run the application I get this error

the error in if statment

if ( username.isEqualToString("")||
            useremail.isEqualToString("") ||