Swift中将数字转换成16进制和2进制都非常的简单:

var convert=String(10,radix:2)
convert=String(16,radix:16)
print("\(convert)")

同样的也可以将二进制数字转换成十进制:

二进制转换

func binaryPosition(position:NSInteger)->NSInteger {
    var result=1
    for _  in 0..<position {
        result = result*2
    }
    return result
}

func convertBinaryToDecimal(binaryNumber:String)->NSInteger {
    var result=0
    var temp:NSInteger
    var power:NSInteger
    for index in 0..<binaryNumber.characters.count {
        temp = Int(binaryNumber[index] as String)!
        power = binaryNumber.characters.count-1-index
        result = result+temp*binaryPosition(power)
    }
    return result
}

func convertNumberToHex(number:NSInteger)->String{
    if number<=0 {
        return "0"
    }
    var result:String = ""
    var num = number
    while(num != 0){
        result=String(num%2)+result
        num=num/2
    }
    return result
}

测试代码:

var binaryNumber="1111"
var resultValue=convertBinaryToDecimal(binaryNumber)
print("\(binaryNumber)的值:\(resultValue)")

var binaryHex=convertNumberToHex(resultValue)
print("FlyElephant:\(binaryHex)")

16进制转换

16进制的转换成数字需要自己定义函数实现，实现方式如下:

func converHexToDecimal(number:String,radix:NSInteger)->NSInteger? {
    let digits = "0123456789abcdefghijklmnopqrstuvwxyz"
    var result=0
    for digit in number.lowercaseString.characters {
        if let range = digits.rangeOfString(String(digit)) {
            let index: Int = digits.startIndex.distanceTo(range.startIndex)
            if index>radix {
                return nil
            }
            result=result*radix+index
        }
    }
    return result
}

var convert=String(100,radix:16)
print("FlyElephant-100的进制值:\(convert)")

var  decimalNumber=converHexToDecimal(convert, radix: 16)
print("FlyElephant-\(convert)的十进制\(decimalNumber!)")

FlyElephant.png