如何快速检查UIImage是否为空？

Question

This is my code but it seems the conditional "if" check for UIImage being empty is not executing. Is it the wrong way of checking if UIImage is empty? I have also tried

if allStyleArrays[i][ii][iii] as UIImage? == nil {
  ...
}

And not working, please if none of those methods checks, what is the correct way?

Thanks.

Code:

for var i = 0; i <= allStyleArrays.count; i++ {

                if i == allStyleArrays.count {
                self.performSegueWithIdentifier("toStylistReviewAndConfirm", sender: self)

            } else {

            for var ii = 0; ii < allStyleArrays[i].count; ii++ {

                for var iii = 0; iii < allStyleArrays[i][ii].count; iii++ {

                    if allStyleArrays[i][ii][iii] as UIImage? == UIImage(named: "") {

                    } else {

                        switch i {
                        case 0:
                            styleN[0].append(allStyleArrays[i][ii][iii])
                            //print("style 1 \(style1.count)")
                            break

                        case 1:
                            styleN[1].append(allStyleArrays[i][ii][iii])
                            //print("style 2 \(style2.count)")
                            break

                        default:
                            styleN[2].append(allStyleArrays[i][ii][iii])
                            //print("style 3 \(style3.count)")
                            break
                        }

                    }

                }

            }

        }

    }

Answer 1

尝试

if allStyleArrays[i][ii][iii].imageAsset == nil