swift学习之数组、字典和字符串

数组、字典、字符串都比oc省略了“@”

数组

var arr:Array = [1,2,3,4]//遍历数组for number in arr{    print(number)}//数组增加arr.append(5)//数组的排序let sortArr = arr.sort { (first, second) -> Bool in    return first>second //（有大到小排序）}print(sortArr)//数组的删除arr.removeFirst()   //删除第一个arr.removeLast()    //删除最后一个arr.removeAtIndex(1) //删除索引为1的arr.removeAll()   //删除全部

字典

//创建字典var dict:Dictionary = ["name":"xiaoming","age":4]//获取valuevar nameStr = dict["name"]//遍历字典 会把key赋值第一个参数，value赋值第二参数for(key,value) in dict{    print(key)    print(value)}//增加key/valuedict["gender"]="男"//更新key/valuedict["age"] = 10//删除//dict.removeAll()  //删除全部dict.removeValueForKey("gender")//合并字典var dict2 = ["height":150]for(key,value) in dict2{    dict[key] = value}

字符串

//字符串的初始化var str:String = "hellow Swift"var str2 = "222"//字符串的拼接和格式化str += str2let number = 100let name = "你刚回来了"//拼接其他类型var str3:String = "name = \(name),age = \(number)"//oc形式的拼接方法var str4 = String(format: "%@,%@", arguments: ["xiao","ming"])//字符串额截取（字符串和oc的字符串可以无缝连接）//装换oc的字符串可以使用oc的一些截取的方法var  str5:NSString = "你刚回来了"var  str6 = "你刚回来了" as NSStringvar substr = str6.substringWithRange(NSMakeRange(0, 4))//swift的字符的截取var str7 = "你刚回来了234567890"// let index = advance(s.startIndex, 5)  swift 1.x//let index2 = advance(s.endIndex, -6); swift 1.xlet index = str7.startIndex.advancedBy(5) //swift 2.0+let index2 = str7.endIndex.advancedBy(-2) //swift 2.0+var range = Range<String.Index>(start: index,end: index2)//从什么地方开始截取（从index开始，不包含index的字符）var subStr1 = str7.substringFromIndex(index);//从0开始截取 到字符串中长度的减6的位置结束（不包含index2）var subStr2 = str7.substringToIndex(index2);//从index的位置到index2的位置（不包含index和index2的位置）var substr3 = str7.substringWithRange(range);//遍历字符for c in str4.characters{    print(c)//从什么地方开始截取（从index开始，不包含index的字符）}