我在想下面的语法:
extension Dictionary where Key:String,Value:String{
func addIfNew(key:String,value:String){
print("new item added: \(key) with value: \(value)")
}
}
例如:该函数将记录任何新添加的数据
最佳答案
这应该够了......
protocol P {}
extension String: P {}
extension Dictionary where Key:P, Value:P {
func addIfNew(key:String, value:String){
print("new item added: \(key) with value: \(value)")
}
}
let d:[String:String] = [:]
不要让其他类型符合 P 就可以了
在 Swift3 中
extension Dictionary where Key == String, Value == String {
func addIfNew(key:String, value:String){
print("new item added: \(key) with value: \(value)")
}
}
let d:[String:String] = [:]
d.addIfNew(key: "a", value: "A")
关于ios - 如何扩展 K :String and V:String 的 Swift 字典，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/35813877/