快速将字符和字符串输入字典

Question

我将如何编写一个函数，该函数接受一个字符串数组并输出一个字典，其中每个字符串的第一个字符作为键，其余字符作为对象？

Answer 1

为您编写这段代码，而没有从您身边看到任何试验，只是因为您是 StackOverflow 的新手。我看到来自 StackOverflow 的消息：“Corey Townsend 是一位新的贡献者。Be nice...” 因此，我只是对您表示欢迎，这是您的代码。

let arr = ["car", "cat", "dog", "ball", "flower", "notebook", "fire"]

func createDictionaryFromArrayAsCoreyWants(arr:[String]) -> [String:String] {

    var dict:[String:String] = [:]
    arr.forEach({ (word:String) in

        let strKey = String(word.prefix(1))
        let startIndex: String.Index = word.index(word.startIndex, offsetBy: 1)
        let strValue = String(word[startIndex..<word.endIndex])
        dict[strKey] = strValue
        print(strKey + " : " + strValue)
    })

    return dict
}

let d = createDictionaryFromArrayAsCoreyWants(arr: arr)
print(d)

加法

刚刚看到“Alex Bailer”对另一个答案的评论，因此为您添加了一个更多功能。享受...

func createDictionaryFromArrayAsCoreyWants(arr:[String]) -> [String:[String]] {

    var dict:[String:[String]] = [:]
    arr.forEach({ (word:String) in

        let strKey = String(word.prefix(1))
        let startIndex: String.Index = word.index(word.startIndex, offsetBy: 1)
        let strValue = String(word[startIndex..<word.endIndex])
        if let a = dict[strKey] {
            dict[strKey] = a + [strValue]
        } else {
            dict[strKey] = [strValue]
        }
        print(strKey + " : " + strValue)
    })

    return dict
}

let d = createDictionaryFromArrayAsCoreyWants(arr: arr)
print(d)

输出：

["d": ["og"], "n": ["otebook"], "b": ["all"], "c": ["ar", "at"], "f": ["lower", "ire"]]

Answer 2

这就是你要找的东西吗？

let d = Dictionary(grouping: array, by: {$0.prefix(1)})

带数组：

let array = ["car", "cat", "dog", "ball", "flower", "notebok", "fire"]

打印出来：

["b": ["ball"], "f": ["flower", "fire"], "d": ["dog"], "c": ["car", "cat"], "n": ["notebok"]]

然后，从值中删除第一个字母：

for key in d.keys {
    let values = d[key]

    let start = String.Index(encodedOffset: 1)
    d[key] = values?.compactMap({ String($0[start...]) })
}

输出：

["f": ["lower", "ire"], "d": ["og"], "b": ["all"], "c": ["ar", "at"], "n": ["otebok"]]