本文的Swift语言版本,1.2
先看看问题
把这两个数组合成一个字典
score = [1,2,3,4,5,6,7,8,9]
dates =["7/12/15","7/12/15","7/13/15"," 7/14/15"]
期望的合成后结果
var scoreDatesDictionary = [
"7/12/15": [1,4]
"7/13/15": [5,8]
"7/14/15": [9]
]
我给出的答案:能解决问题,但是不够优雅,不够简洁,因为我对Swift很多global的函数掌握的不是很好,最近开发项目还是用OC。以后遇到了我没掌握好的,就用博客记录下来。
let score = [1,9,]
let dates = ["7/12/15"," 7/14/15"]
var dic = [String:[Int]]()
for var index=0;index < dates.count; index++ {
let key = dates[index];
var value = dic[key]
if value == nil{
dic[key] = [score[index]]
}else{
value!.append(score[index])
dic[key] = value
}
}
println(dic)
参考答案
let score = [1,9]
let dates = ["7/12/15"," 7/14/15"]
var dic = [String:[Int]]()
for (index,date) in enumerate(dates) {
dic[date] = (dic[date] ?? []) + [score[index]]
}
print(dic) // prints "[7/12/15: [1,2,3,4],7/14/15: [9],7/13/15: [5,6,7,8]]"
enumerate 函数-Swift 1.2
遍历数组和字符串的方式,同时返回index以及数据
let str = "Wenchen"
for (index,character) in enumerate(str){
println("\(index):\(character)")
}
0:W
1:e
2:n
3:c
4:h
5:e
6:n
遍历数组的例子
let myArray = ["Wen","Chen","Huang"]
for (index,str) in enumerate(myArray){
println("\(index):\(str)")
}
0:Wen
1:Chen
2:Huang