swift基础--数组、字典

2023-07-28 17:46:16

（1）初始化

（2）新增、修改、删除

（3）清空

（4）遍历

var array1 = ["x","y","z"]
var array2:[String] = ["x","y","z"]
var array3:Array<String> = ["x","y","z"]
array1[0]
array1[1]
//初始化
var array4 = []//不建议使用此方法进行初始化，可以用来清空数组
var array5 = [Int]()
var array6 = Array<String>()
//新增、修改、删除
array6.append("x")
array6.append("y")
array6.append("z")
array6 = []//清空数组
array6
array6.isEmpty
array6 += ["m"]
array6.insert("n", atIndex: 0)
array6
array6.removeAtIndex(0)
array6
array6.removeLast()
array1[0]
array1[1...2] = ["a","b","c"]
array1[0...2] = ["a"]
//遍历
for (index,item) in enumerate(array1){
println("index : \(index) value : \(item)")
}

（1）初始化

（2）新增、修改、删除、查询

（3）遍历

var dict1:Dictionary<String,String> = ["ak":"av","bk":"bv","ck":"cv"]
var dict2:Dictionary<Int,String> = [1:"av",5:"bv",6:"cv"]
dict1["ak"]
dict1["bk"]
dict2[5]
dict2[6]
dict2
//初始化
var dict3 = Dictionary<String,String>()
var dict4 = [String:String]()
dict4
//清空
dict2 = [:]
//数组数量、根据键获取值
dict1.count
dict1["ak"]! + "x"//可选型
//修改
dict1["ak"] = "aav"
dict1.updateValue("aaaav", forKey: "ak")
//新增
dict1["dk"] = "dk"
//删除
dict1["dk"] = nil
dict1.removeValueForKey("dk")
for (key,value) in dict1 {
println("key \(key), value \(value)")
}
Array(dict1.keys)
dict1.values