Swift - 13 - 字符串和Character

//: Playground - noun: a place where people can play

import UIKit

var str = "hi"

// 字符串拼接
str += ", rinpe"
str += ", lili"

// 创建一个空的字符串
var nullStr = String()
var nullStr2 = ""

// 判断一个字符串是否为空
nullStr.isEmpty

// 字符串遍历
for string in str.characters {
    string
}

// Charater
var ch:Character = "