Convert between Decimal, Binary and Hexadecimal in Swift

Both String and Int have initializers which take a radix (base). Combining those, you can achieve all of the conversions:

// Decimal to binarylet d1 = 21let b1 = String(d1, radix: 2)print(b1) // "10101"// Binary to decimallet b2 = "10110"let d2 = Int(b2, radix: 2)!print(d2) // 22// Decimal to hexadecimallet d3 = 61let h1 = String(d3, radix: 16)print(h1) // "3d"// Hexadecimal to decimallet h2 = "a3"let d4 = Int(h2, radix: 16)!print(d4) // 163// Binary to hexadecimallet b3 = "10101011"let h3 = String(Int(b3, radix: 2)!, radix: 16)print(h3) // "ab"// Hexadecimal to binarylet h4 = "face"let b4 = String(Int(h4, radix: 16)!, radix: 2)print(b4) // "1111101011001110"

Swift Converter 2, 8, 10, 16

A bunch of Int and String is used to convert different systems.

Int is used for working with decimal
String is used for other types

It is safe to convert a string representation of system to decimal and decimal to string representation

String -> Int -> String

There are samples of

binary(2) - 0boctal(8) - 0odecimal(10)hexadecimal(16) - 0x

extension Int {        //From Decimal    //10 -> 2    func decToBinString() -> String {        let result = createString(radix: 2)        return result    }        //10 -> 8    func decToOctString() -> String {//        let result = decToOctStringFormat()        let result = createString(radix: 8)                return result    }        //10 -> 16    func decToHexString() -> String {//        let result = decToHexStringFormat()        let result = createString(radix: 16)        return result    }        //10 -> 8    func decToOctStringFormat(minLength: Int = 0) -> String {        return createString(minLength: minLength, system: "O")    }    //10 -> 16    func decToHexStringFormat(minLength: Int = 0) -> String {        return createString(minLength: minLength, system: "X")    }        fileprivate  func createString(radix: Int) -> String {        return String(self, radix: radix, uppercase: true)    }        fileprivate func createString(minLength: Int = 0, system: String) -> String {        //0 - fill empty space by 0        //minLength - min count of chars        //system - system number        return String(format:"%0\(minLength)\(system)", self)    }}

extension String {        //To Decimal    //2 -> 10    func binToDec() -> Int {        return createInt(radix: 2)    }        //8 -> 10    func octToDec() -> Int {        return createInt(radix: 8)    }        //16 -> 10    func hexToDec() -> Int {        return createInt(radix: 16)    }        //Others    //2 -> 8    func binToOct() -> String {        return self.binToDec().decToOctString()    }        //2 -> 16    func binToHex() -> String {        return self.binToDec().decToHexString()    }        //8 -> 16    func octToHex() -> String {        return self.octToDec().decToHexString()    }        //16 -> 8    func hexToOct() -> String {        return self.hexToDec().decToOctString()    }        //16 -> 2    func hexToBin() -> String {        return self.hexToDec().decToBinString()    }        //8 -> 2    func octToBin() -> String {        return self.octToDec().decToBinString()    }    //Additional    //16 -> 2    func hexToBinStringFormat(minLength: Int = 0) -> String {                return hexToBin().pad(minLength: minLength)    }        fileprivate func pad(minLength: Int) -> String {        let padCount = minLength - self.count                guard padCount > 0 else {            return self        }        return String(repeating: "0", count: padCount) + self    }     fileprivate func createInt(radix: Int) -> Int {        return Int(self, radix: radix)!    }    }

Tests:

func testConverter() {    let decInt = 13511    let binStr = "11010011000111"    let octStr = "32307"    let hexStr = "34C7"        //From Decimal    //10 -> 2    XCTAssertEqual(binStr, decInt.decToBinString())    //10 -> 8    XCTAssertEqual(octStr, decInt.decToOctString())    //10 -> 16    XCTAssertEqual(hexStr, decInt.decToHexString())        //To Decimal    //2 -> 10    XCTAssertEqual(decInt, binStr.binToDec())    //8 -> 10    XCTAssertEqual(decInt, octStr.octToDec())    //16 -> 10    XCTAssertEqual(decInt, hexStr.hexToDec())        //Others    //2 -> 8    XCTAssertEqual(octStr, binStr.binToOct())    //2 -> 16    XCTAssertEqual(hexStr, binStr.binToHex())    //8 -> 16    XCTAssertEqual(hexStr, octStr.octToHex())    //16 -> 8    XCTAssertEqual(octStr, hexStr.hexToOct())    //16 -> 2    XCTAssertEqual(binStr, hexStr.hexToBin())    //8 -> 2    XCTAssertEqual(binStr, octStr.octToBin())    //String format feature    //10 -> 8    XCTAssertEqual("017", (15).decToOctStringFormat(minLength: 3))    //10 -> 16    XCTAssertEqual("00F", (15).decToHexStringFormat(minLength: 3))    //16 -> 2    XCTAssertEqual("0011010011000111", hexStr.hexToBinStringFormat(minLength: 16))    }

from decimal to binary

extension Int {    //10 -> "2"    func decToBinString() -> String {        return String(self, radix: 2, uppercase: true)    }}extension String {    //"2" -> 10    func binToDec() -> Int {        return Int(self, radix: 2)!    }}