iOS 将十进制转化为十六进制、十进制转二进制

//将十进制转化为十六进制

- (NSString *)ToHex:(uint16_t)tmpid

{

NSString *nLetterValue;

NSString *str =@”“;

uint16_t ttmpig;

for (int i = 0; i<9; i++) {

ttmpig=tmpid%16;

tmpid=tmpid/16;

switch (ttmpig)

{

case 10:

nLetterValue =@”A”;break;

case 11:

nLetterValue =@”B”;break;

case 12:

nLetterValue =@”C”;break;

case 13:

nLetterValue =@”D”;break;

case 14:

nLetterValue =@”E”;break;

case 15:

nLetterValue =@”F”;break;

default:

nLetterValue = [NSString stringWithFormat:@”%u”,ttmpig];

}
str = [nLetterValue stringByAppendingString:str];
if (tmpid == 0) {
break;
}

}

return str;}

//十进制转二进制

- (NSString *)toBinarySystemWithDecimalSystem:(NSInteger)decimal

{

NSInteger num = decimal;//[decimal intValue];

NSInteger remainder = 0; //余数

NSInteger divisor = 0; //除数

NSString * prepare = @”“;

while (true)

{

remainder = num%2;

divisor = num/2;

num = divisor;

prepare = [prepare stringByAppendingFormat:@”%ld”,remainder];

if (divisor == 0)

{

break;

}

}

NSString * result = @”“;

for (NSInteger i = prepare.length - 1; i >= 0; i –)

{

result = [result stringByAppendingFormat:@”%@”,

[prepare substringWithRange:NSMakeRange(i , 1)]];

}

return result;

}