【Java-算法】 十六進制轉字節數組

Java Code

public class Convert{

    public static void main(String args[]) {
        String sHex = "00 B6 00 02 0A 28"; // 輸入十六進制字符串
        sHex = sHex.replace(" ", ""); // 去掉空格
        byte[] bytes = hexStringToBytes(sHex); // 十六進制轉字節數組
        for (byte b : bytes) {
            System.out.print(b + " "); // 字節數組逐個打印出來
        }
    }

    /** 十六進制轉換成字節數組 */
    private static byte[] hexStringToBytes(String hexString) {
        if (hexString == null || hexString.equals("")) {
            return null;
        }
        hexString = hexString.toUpperCase(); // 十六進制轉大寫字母
        int length = hexString.length() / 2; // 獲取十六進制的長度，2個字符爲一個十六進制
        char[] hexChars = hexString.toCharArray();
        byte[] d = new byte[length];
        for (int i = 0; i < length; i++) {
            int pos = i * 2;
            d[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
        }
        return d;
    }

    /** char轉byte */
    private static byte charToByte(char c) {
        return (byte) "0123456789ABCDEF".indexOf(c);
    }
}

輸出結果：0 -74 0 2 10 40