1 /** 2 * 把十六進位制數字轉換為十進位制數字 3 * @param hexSrcStr 4 * @return 5 * 170 6 */ 7 public static String convertHex2Decimal(String hexSrcStr){ 8 if (hexSrcStr==null || hexSrcStr.trim().length()==0){ 9 return null; 10 } 11 if (!hexSrcStr.startsWith("0x")){ 12 System.out.println("十六進位制數字輸入非法!"); 13 return null; 14 } 15 String substring1 = hexSrcStr.substring(2); 16 for (int i = 0; i < substring1.length(); i++) { 17 char charAt = substring1.charAt(i); 18 if (!(Character.isDigit(charAt) || (Character.isUpperCase(charAt) && charAt >= 'A' && charAt <= 'F'))){ 19 return null; 20 } 21 } 22 23 HashMap<Character, Integer> characterIntegerHashMap = new HashMap<>(); 24 characterIntegerHashMap.put('A',10); 25 characterIntegerHashMap.put('B',11); 26 characterIntegerHashMap.put('C',12); 27 characterIntegerHashMap.put('D',13); 28 characterIntegerHashMap.put('E',14); 29 characterIntegerHashMap.put('F',15); 30 31 // 0xAA 32 String substring = hexSrcStr.substring(2); 33 int length = substring.length(); 34 int sum=0; 35 int ret=1; 36 for (int i = length-1; i >=0 ; i--) { 37 if (i==0){ 38 ret=1; 39 }else { 40 for (int j =0;j<i;j++) { 41 ret*=16; 42 } 43 } 44 45 char charAt = substring.charAt((length-1)-i); 46 Integer integer=0; 47 Integer integer1=0; 48 if (Character.isDigit(charAt)){ 49 String charStr = String.valueOf(charAt); 50 integer = Integer.valueOf(charStr); 51 integer*=ret; 52 }else if (Character.isUpperCase(charAt)){ 53 integer1 = characterIntegerHashMap.get(charAt); 54 integer1*=ret; 55 } 56 57 if (Character.isDigit(charAt)){ 58 sum+=integer; 59 ret=1; 60 }else if (Character.isUpperCase(charAt)){ 61 sum+=integer1; 62 ret=1; 63 } 64 } 65 66 return String.valueOf(sum); 67 }