//: Playground - noun: a place where people can play import UIKit var dict = [1:"one", 2:"two", 3:"three", 4:"four"] dict.count
dict.isEmpty dict[1]
dict[66] "课程名称: " + dict[1]! // 添加和修改
dict[5] = "five"
dict[4] = "44444"
dict.updateValue("2222", forKey: 2);
dict // 删除
dict[1] = nil;
dict.removeValueForKey(5)
dict // 遍历
for (key, value) in dict {
print("key:\(key) value:\(value)")
} dict.keys
dict.values for key in dict.keys {
print(key)
} for value in dict.values {
print(value)
}