Question

Objective-C中，NSString和Byte的转换

NSString *str = @"AA21f0c1762a3abc299c013abe7dbcc50001DD"
怎么将里面的字符转换到Byte数组中，如下
Byte buffer[] = { 0xAA, 0x21, 0xf0, 0xc1, 0x76, 0x2a, 0x3a, ... , 0x01, 0xDD }
各位大侠恳请帮帮忙，先谢谢啦
找到答案了，
@interface NSString (NSStringHexToBytes)
-(NSData*) hexToBytes ;
@end
@implementation NSString (NSStringHexToBytes)
-(NSData*) hexToBytes {
NSMutableData* data = [NSMutableDatadata];
int idx;
for (idx = 0; idx+2 <= self.length; idx+=2) {
NSRange range = NSMakeRange(idx, 2);
NSString* hexStr = [selfsubstringWithRange:range];
NSScanner* scanner = [NSScannerscannerWithString:hexStr];
unsignedint intValue;
[scanner scanHexInt:&intValue];
[data appendBytes:&intValue length:1];
}
return data;
}
@end

应用：
NSData *data = [str hexToBytes];

Answer 1

NSString *str = @"AA21f0c1762a3abc299c013abe7dbcc50001DD";

NSData* bytes = [str dataUsingEncoding:NSUTF8StringEncoding];
Byte * myByte = (Byte *)[bytes bytes];
NSLog(@"myByte = %s",myByte);