arrays - 如何检查 ANY 的数组包含哪种数据类型的元素

Question

我有一个类似于[Any] 的数组，我只是附加了一些String 元素和UIImage 元素。最后，我将它列在 UITableView 中，我需要在其中显示图像，其中数组索引具有 UIImage 和字符串，其中元素索引具有 String类型。

class PhotosVC: UIViewController {

    var arrPhotos: [Any] = [Any]()

    override func viewDidLoad() {
        self.arrPhotos.append("stringValue")
        self.arrPhotos.append(pickedImage)
        self.collectionViewData.reloadData()
    }
}
extension PhotosVC: UICollectionViewDataSource, UICollectionViewDelegate, UICollectionViewDelegateFlowLayout {

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return arrPhotos.count
    }
    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "PhotosDescCell", for: indexPath) as! PhotosDescCell

        if arrPhotos[indexPath] == String { // how to check here is element is String type or UIImage
            cell.lblDesc.text = arrPhotos[indexPath] as? String
        }
        else {
            cell.imgPhotos.image = arrPhotos[indexPath.row] as? UIImage
        }
        return cell
    }
}

Answer 1

只需使用is

  func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "PhotosDescCell", for: indexPath) as! PhotosDescCell

        if arrPhotos[indexPath] is String { 
            cell.lblDesc.text = arrPhotos[indexPath] as? String
        }
        else {
            cell.imgPhotos.image = arrPhotos[indexPath.row] as? UIImage
        }
        return cell
    }