javascript - 将 5 位二进制字符串解码回字符

Question

我创建了一个简单的函数，可以将每个字母字符 (a-z) 转换为 always 5-digit binary string (like "00000->a"或“11000->y”)

SWIFT:

 let alphabeth_array=["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "", "", "", "", "", ""]
 for i in 0..<32 {
   let binary_code = String(i/16%2) + String(i/8%2) + String(i/4%2) + String(i/2%2) + String(i%2)
   print("\(alphabeth_array[i]) : \(binary_code)")
}

---

JavaScript:

 var alphabeth_array=["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "", "", "", "", "", ""]
 for (var i=0; i<32; i++) {
   var binary_code = (i/16%2).toString() + (i/8%2).toString() + (i/4%2).toString() + (i/2%2).toString() + (i%2).toString()
   console.log(alphabeth_array[i] + " : " + binary_code)
}

---

但现在我想将二进制字符串解码回它们从 alphabeth_array 中连接的字符，您可以在上面找到。

SWIFT:

let binary = "00000" //starting with the binary string
let character = getChar(binaryCode: binary)

func getChar(binaryCode: String) -> (String) {
   // programm logic
   return result
}

---

JavaScript:

var binary = "00000" //starting with the binary string
var character = getChar(binary)


function getChar(binary) {
   // programm logic
   return result
}

我完全不知道如何反转解码函数以将二进制字符串转换回连接的字符。任何帮助将不胜感激，谢谢! (我更愿意只获取一些小代码片段，Swift 或 javascript - 哪种语言无关紧要 !)

Answer 1

您可以使用 init?<S>(_ text: S, radix: Int = default) where S : StringProtocol初始化程序将二进制字符串转换为整数，并将其用作访问字母数组元素的索引。您也可以使用 String(_ value:, radix:, uppercase:) 将数组索引转换为二进制的初始化程序:

let alphabeth = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]
var bins: [String] = []
for index in alphabeth.indices {
    let binary = String(index, radix: 2)
    let zeros = repeatElement("0", count: 5 - binary.count).joined()
    bins.append("\(zeros)\(binary)")
    print(alphabeth[index], bins.last!)
}
for binary in bins {
    if let index = Int(binary, radix: 2) {
        print(alphabeth[index])
    }   
}