swift中的字典

定义一个字典：

var dict = Dictionary()  ——空字典！

或者  var dity:Dictionary= [“key1”:“www”,“key2”:“aaaa”,“key3”:“dddd”]

1.给字典中存储数据

dict.updateValue(value: Value, forKey: Key)

dict[2] = "B";

dict[3] = "C";

2.移除字典中的数据

dict.removeAll();

dict.removeAll(keepCapacity: true);

3.通过Key查找value元素

  dict[Key]

4.遍历字典

///遍历字典的Key和Value

for (key,value) in dict {

    print("\(key): \(value)")

}

///遍历字典的Key

for dictKeys in dict.keys {

    print("dict.keys: \(dictKeys)")

}

///遍历字典的Value

for dictValues in dict.values {

  print("dict.values: \(dictValues)")

}