美文网首页收藏swiftSwift5.2连载
iOS Swift4.0 数组Array的使用

iOS Swift4.0 数组Array的使用

作者: _菩提本无树_ | 来源:发表于2018-01-23 10:59 被阅读331次

上代码

1.定义数组

func definitionArr()->(){
    #if false
    var arr:[Any] = []//空 任意类型
    var arr1:[String] = []//空 只能存字符串
    var arr2:[Any] = ["1",1]
    var arr4:[Dictionary] = []
        
    let arr3 = ["1",2] as Any
    #endif
}

2.删除数组元素

func remove() -> () {
    var arr = ["今","天","是","个","好","日","子","A","b"]
    //删除指定index的元素
    //arr.remove(at: 2)
    //删除最后的一个元素
    //arr.removeLast()
    //删除最前的一个元素
    //arr.removeFirst()
    //单侧删除
    //arr.removeFirst(3)
    //单侧删除
    //arr.removeLast(3)
    //删除所有的元素
    //arr.removeAll()
    //是否保留arr的空间
    arr.removeAll(keepingCapacity: true)
    print(arr)
}

3.插入

func insertElement() -> () {
    var arr = ["今","天","是","个","好","日","子","A","b"]
    //插入数据
    arr.insert("1", at: 0)
    //print(arr)
}

4.添加元素

func addElement() -> () {
    let arr1 = ["今","天","是","个","好","日","子"]
    var arr = ["今","天","是","个","好","日","子","A","b"]
    //添加数组
    arr.append(contentsOf: arr1)
    //print(arr)
}

5.数组去重

 func arrRemovingWeight() -> () {
    //数组去重
    #if false
        //方法1
        let array = [111, 222, 111]
        var dictInts = Dictionary<String, Int>()
        
        for number in array {
            dictInts[String(number)] = number
        }
        
        var result = [Int]()
        for value in dictInts.values {
            result.append(value)
        }
        print(result)
    #endif
    #if false
    //方法2
    let arr = ["1","2","3","4","3"]
    var arr1:[String] = []
    for item in arr {
        
        if !arr1.contains(item){
            arr1.append(item)
        }
    }
    print(arr1)
    #endif
    //数组合并 只要不同的和只要相同的只需要在if的位置加判断即可
    let arr = ["1","2","3","4"]
    var arr1 = ["1","2","4","8"]
    
    for item in arr {
        if !arr1.contains(item){
            arr1.append(item)
        }
    }
    //print(arr1)

    //判断数组是否为空
    if arr1.isEmpty {
        
    }
    
}

5.0数组的其他用法

func arrOterMethed() -> () {
    //数组的其他用法
    //删除数组
    let arr = ["1","2","4","8"]
    var arr1 = ["1","2","4","8"]
    arr1.remove(at: 0)
    //删除指定的元素
    if arr1.contains("2") {
        let index = arr1.index(of: "2")
        arr1.remove(at: index!)
    }
    //使用数据
    arr1[0] = arr[3]
    
    print(arr1)
    
    //数组降序
    var arr3 = [2,4,1,6,9,5,4,9]
    let count = arr3.count
    var arr5:[Int] = []
    let mix = arr3.min()
    let max = arr3.max()
    for _ in 0..<count {
        arr5.append(disposeData(arr: arr3))
        let index = arr3.index(of: arr3.max()!)
        arr3 .remove(at: index!)
    }
    print(String(describing: arr5))
    print("最大:\(String(describing: max))最小值:\(String(describing: mix))")
    //数组存数组套字典
    let arr4:Array<Array<Dictionary<String,String>>> = [[["name":"董"]]]
    let arr6:Array<Dictionary> = arr4[0]
    let dict:Dictionary = arr6[0]
    print(dict["name"]!)

    //数组的降序
    let usernames = ["Lves", "Wildcat", "Lecoding","Cc"]
    //数组的升序
    let arr9:Array<String> = ["name","aler","ved","red","whie","pokm"]
    let arr8:Array<String> = arr9.reversed()
    print(arr8)
    

    let resultName1 = usernames.sorted(by: backWards)
    //数组的容量类似于count
    let resultName2 = usernames.capacity
    let user = ["Lves", "Wildcat", "Cc", "Lecoding"]
    //用来判断两个队列的是否拥有相同的元素,并且顺序是一致的
    let resultName3 = usernames.elementsEqual(user)
    //判断两个数组是否一样并且顺序是一致的
    let re = usernames.starts(with: user)
    
    print(resultName1,re)
}
func backWards(s1: String, s2: String) -> Bool
{
    return s1 > s2
}

func disposeData(arr :Array<Any>) -> Int {
    let arr1:[Int] = arr as! [Int]
    let max = arr1.max()
    return max!
}

相关文章

  • iOS Swift4.0 数组Array的使用

    上代码 1.定义数组 2.删除数组元素 3.插入 4.添加元素 5.数组去重 5.0数组的其他用法

  • JS随写:A组rray数

    Array数组 创建数组的两种方式: 使用Array构造函数 var colors = new Array() ,...

  • JS数组常用方法

    Array数组类型 数组的每一项都可以保存任何类型的数据,创建数组的方法可以使用Array构造函数 使用Array...

  • IOS 数组的一些操作

    ios可变数组的所有操作 #pragma mark 创建数组c NSMutableArray * array =[...

  • PHP入门之:数组、常量、数据类型

    一数组1 自定义数组 索引数组(枚举数组) 定义方法一:使用array方法: ①索引数组(枚举数组):array(...

  • Numpy学习-1

    Numpy学习-1 数组基础 创建数组1 .一维数组的创建 从上看出:使用array()函数创建数组,array的...

  • js数组

    数组 使用Array构造函数来实现数组var arr = new Array();//空数组var arr = n...

  • js数组

    JS数组的创建: 1,使用Array数组的方式: var arrayObj = new Array();//创建一...

  • js Array.from 初始化默认值

    Array.from 将伪数组转换成数组可使用Array的方法如forEach等 Array.from(array...

  • PHP判断是关联数组还是索引数组的方法

    实现思想 使用array_values()函数获取指定数组的全部键值,将其转为索引数组使用array_diff_k...

网友评论

  • 麒缘伊声:有数组截取某一段的方法吗
    _菩提本无树_:/// The array's "past the end" position---that is, the position one greater
    /// than the last valid subscript argument.
    ///
    /// When you need a range that includes the last element of an array, use the
    /// half-open range operator (`..<`) with `endIndex`. The `..<` operator
    /// creates a range that doesn't include the upper bound, so it's always
    /// safe to use with `endIndex`. For example:
    ///
    /// let numbers = [10, 20, 30, 40, 50]
    /// if let i = numbers.index(of: 30) {
    /// print(numbers[i ..< numbers.endIndex])
    /// }
    /// // Prints "[30, 40, 50]"
    ///
    /// If the array is empty, `endIndex` is equal to `startIndex`.
    _菩提本无树_:暂时未找到有这个方法

本文标题:iOS Swift4.0 数组Array的使用

本文链接:https://www.haomeiwen.com/subject/hbtsaxtx.html