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Summary of some new changes in collection data structures in Swift 3.0
Summary of some new changes in collection data structures in Swift 3.0
1. Changes to Array
The modified API example in array array is as follows:
//创建大量相同元素的数组
//创建有10个String类型元素的数组，并且每个元素都为字符串"Hello"
//swift2.2
//var array3 = [String](count: 10, repeatedValue: "Hello")
//swift3.0
var array3 = [String](repeating: "Hello", count: 10)
//创建有10个Int类型元素的数组，且每个元素都为1
//swift2.2
//var array4 = Array(count: 10, repeatedValue: 1)
//swift3.0
var array4 = Array(repeating: 1, count: 10)
var array = [1,2,3,4,5,6,7,8,9]
//向数组中追加一组元素
//swift2.2
//array.appendContentsOf([11,12,13])
//swift3.0
array.append(contentsOf: [11,12,13])
//向数组中的某个位置插入一个元素
//swift2.2
//array.insert(0, atIndex: 0)
//swift3.0
array.insert(0, at: 0)
//向数组中的某个位置插入一组元素
//swift2.2
//array.insertContentsOf([-2,-1], at: 0)
//swift3.0
array.insert(contentsOf: [-2,-1], at: 0)
//移除数组中某个位置的元素
//swift2.2
//array.removeAtIndex(1)
//swift3.0
array.remove(at: 1)
//移除一个范围内的元素
//swift2.2
//array.removeRange(0...2)
//swift3.0
array.removeSubrange(0...2)
//修改一个范围内的元素
//swift2.2
//array.replaceRange(0...2, with: [0,1])
//swift3.0
array.replaceSubrange(0...2, with: [0,1])
//进行数组枚举遍历 将输出 (0,0) (1,1) (2,2) (3,3) (4,4)
//swift3.0 中将枚举属性enumerate 修改为enumerated()方法
for item in arrayLet.enumerated(){
print(item)
}
var arraySort = [1,3,5,6,7]
//获取数组中的最大值
//swift2.2
//arraySort.maxElement()
//swift3.0
arraySort.max()
//获取数组中的最小值
//swift2.2
//arraySort.minElement()
//swift3.0
arraySort.min()
//从大到小排序
//swift2.2
//arraySort = arraySort.sort(>)
//swift3.0
arraySort = arraySort.sorted(isOrderedBefore: >)
//从小到大排序
//swift2.2
//arraySort = arraySort.sort(<)
//swift3.0
arraySort = arraySort.sorted(isOrderedBefore: <)
The modification example in the Set collection is as follows:
//创建set集合
var set1:Set<Int> = [1,2,3,4]
//进行下标的移动
//获取某个下标后一个元素
//swlft2.2
//set1[set1.startIndex.successor()]
//swift3.0
set1[set1.index(after: set1.startIndex)]
//获取某个下标后几位的元素
//swift2.2
//set1[set1.startIndex.advancedBy(3)]
//swift3.0
set1[set1.index(set1.startIndex, offsetBy: 3)]
//获取集合中的最大值
//swift2.2
//set1.maxElement()
//swift3.0
set1.max()
//获取集合中的最小值
//swift2.2
//set1.minElement()
//swift3.0
set1.min()
//移除集合中某个位置的元素
//swift2.2
//set1.removeAtIndex(set1.indexOf(3)!)
//swift3.0
set1.remove(at: set1.index(of: 3)!)
var set3:Set<Int> = [1,2,3,4]
var set4:Set<Int> = [1,2,5,6]
//返回交集 {1，2}
//swift2.2
//var setInter = set3.intersect(set4)
//swift3.0
var setInter = set3.intersection(set4)
//返回交集的补集{3，4，5，6}
//swift2.2
//var setEx = set3.exclusiveOr(set4)
//swift3.0
var setEx = set3.symmetricDifference(set4)
var set5:Set = [1,2]
var set6:Set = [2,3]
var set7:Set = [1,2,3]
var set8:Set = [1,2,3]
//判断是否是某个集合的子集 set5是set7的子集 返回ture
//swift2.2
//set5.isSubsetOf(set7)
//swift3.0
set5.isSubset(of: set7)
//判断是否是某个集合的超集 set7是set5的超集 返回ture
//swift2.2
//set7.isSupersetOf(set5)
//swift3.0
set7.isSuperset(of: set5)
//判断是否是某个集合的真子集 set5是set7的真子集 返回ture
//swift2.2
//set5.isStrictSubsetOf(set7)
//swift3.0
set5.isStrictSubset(of: set7)
//判断是否是某个集合的真超集 set7不是set8的真超集 返回false
//swift2.2
//set7.isStrictSupersetOf(set8)
//swift3.0
set7.isStrictSuperset(of: set8)
The modification example in the Dictionary dictionary is as follows:
//通过键删除某个键值对 //swift2.2 //dic1.removeValueForKey(1) //swift3.0 dic1.removeValue(forKey: 1)
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