Question

我需要与作为登录的Web服务集成。需要在客户端上生成哈希。我能够生成正确的哈希作为NSMutableData，但后来我需要将它转换为字符串，而不会在输出控制台中将NSMutableData对象呈现为字符串时产生空格或括号。我看过几篇帖子，似乎都说了同样的话：


NSString *newstring = [[NSString alloc] initWithDSata:dataToConvert  encoding:NSUTF8StringEncoding];

不幸的是，这对我不起作用。使用NSUTF8StringEncoding返回null。 NSASCIIStringEncoding更糟糕。

这是我的代码：


    NSString *password = [NSString stringWithFormat:@"%@%@", kPrefix, [self.txtPassword text]];
    NSLog(@"PLAIN: %@", password);

    NSData *data = [password dataUsingEncoding:NSASCIIStringEncoding];
    NSMutableData *sha256Out = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
    CC_SHA256(data.bytes, data.length, sha256Out.mutableBytes);
    NSString *preppedPassword = [[NSString alloc] initWithData:sha256Out encoding:NSASCIIStringEncoding];
    NSLog(@"HASH: %@\n", preppedPassword);

如何将NSMutableData转换为字符串？

我的问题是我需要从这个

＆lt; 7e8df5b3 17c99263 e4fe6220 bb75b798 4a41de45 44464ba8 06266397 f165742e＆gt;

到这个

7e8df5b317c99263e4fe6220bb75b7984a41de4544464ba806266397f165742e

Answer 1

请参阅How to convert an NSData into an NSString Hex string?

我自己使用了一个稍微修改过的版本：

@implementation NSData (Hex)

- (NSString *)hexRepresentationWithSpaces:(BOOL)spaces uppercase:(BOOL)uppercase {
    const unsigned char *bytes = (const unsigned char *)[self bytes];
    NSUInteger nbBytes = [self length];
    // If spaces is true, insert a space every this many input bytes (twice this many output characters).
    static const NSUInteger spaceEveryThisManyBytes = 4UL;
    // If spaces is true, insert a line-break instead of a space every this many spaces.
    static const NSUInteger lineBreakEveryThisManySpaces = 4UL;
    const NSUInteger lineBreakEveryThisManyBytes = spaceEveryThisManyBytes * lineBreakEveryThisManySpaces;
    NSUInteger strLen = 2 * nbBytes + (spaces ? nbBytes / spaceEveryThisManyBytes : 0);

    NSMutableString *hex = [[NSMutableString alloc] initWithCapacity:strLen];

    for (NSUInteger i = 0; i < nbBytes; ) {
        if (uppercase) {
            [hex appendFormat:@"%02X", bytes[i]];
        } else {
            [hex appendFormat:@"%02x", bytes[i]];
        }
        // We need to increment here so that the every-n-bytes computations are right.
        ++i;

        if (spaces) {
            if (i % lineBreakEveryThisManyBytes == 0) {
                [hex appendString:@"\n"];
            } else if (i % spaceEveryThisManyBytes == 0) {
                [hex appendString:@" "];
            }
        }
    }
    return hex;
}

@end

将Sha256哈希值转换为NSString

1 个答案: