Swift截断标签替代文本

你可以这样做:

1: 添加扩展名以检查标签是否被截断

extension UILabel {
    var isTruncated: Bool {
        guard let labelText = text else {
            return false
        }
        let labelTextSize = (labelText as NSString).boundingRect(
            with: CGSize(width: frame.size.width, height: .greatestFiniteMagnitude),
            options: .usesLineFragmentOrigin,
            attributes: [NSFontAttributeName: font],
            context: nil).size

        return labelTextSize.height > bounds.size.height
    }
}

2: 添加字典以存储原始字符串

var dict = [Int:Any]()

let label = UILabel(frame: CGRect(x: 0, y: 0, width: 30, height: 50))
label.text = "This is text number A"
label.tag = 0

4: 检查标签是否被截断,如果是,则添加默认值并将原始值存储到dict:

if label.isTruncated {
    dict.updateValue(label.text, forKey: label.tag)
    label.text = "A"
}

let original = dict[0] // for tag 0 for example