Hex NSString to char []

Question

我有一个十六进制NSString,我希望能够将其打包到一个char数组.

例如,我有一个NSString:

NSString* hex = "AABBCCDD";

我希望能够将其转换为char数组以与CCCrypt一起使用:

char bytes[] = { 0xAA, 0xBB, 0xCC, 0xDD };

我怎么能这样做？

Answer 1

您可以使用for循环遍历每个两个字节的十六进制字符.然后,使用NSScanner它将其读入字符数组的char变量.

NSString * hexString = @"AABBCCDD";
char * myBuffer = (char *)malloc((int)[hexString length] / 2 + 1);
bzero(myBuffer, [hexString length] / 2 + 1);
for (int i = 0; i < [hexString length] - 1; i += 2) {
    unsigned int anInt;
    NSString * hexCharStr = [hexString substringWithRange:NSMakeRange(i, 2)];
    NSScanner * scanner = [[[NSScanner alloc] initWithString:hexCharStr] autorelease];
    [scanner scanHexInt:&anInt];
    myBuffer[i / 2] = (char)anInt;
}
...
// use myBuffer here
...
printf("%s\n", myBuffer);
free(myBuffer);

请注意,这仅在hexString长度均匀(即可被2整除)时才有效.