iOS Swift4.0 数组Array的使用

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()
        
        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..>> = [[["name":"董"]]]
    let arr6:Array = 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 = ["name","aler","ved","red","whie","pokm"]
    let arr8:Array = 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) -> Int {
    let arr1:[Int] = arr as! [Int]
    let max = arr1.max()
    return max!
}