我在vb中有一段代码。我需要将字节数组转换为base 64字符串。以下是vb代码。
如果是arrLicence.Count＆gt; 0然后
LicenceBytes = CType（Array.CreateInstance（GetType（Byte），6），Byte（））
LicenceBytes(0) = Convert.ToByte(arrLicence(0).ToString(), 16) LicenceBytes(1) = Convert.ToByte(arrLicence(1).ToString(), 16) LicenceBytes(2) = Convert.ToByte(arrLicence(2).ToString(), 16) LicenceBytes(3) = Convert.ToByte(arrLicence(3).ToString(), 16) LicenceBytes(4) = Convert.ToByte(arrLicence(4).ToString(), 16) LicenceBytes(5) = Convert.ToByte(arrLicence(5).ToString(), 16) LicenceString = Convert.ToBase64String(LicenceBytes) '6 byteArray - passed by the user - Base64Encoded
我需要它在iphone中的等价物。我试过NSData和base64转换，但结果推迟。
我已使用此链接进行转换。 http://www.cocoadev.com/index.pl?BaseSixtyFour
我尝试使用memcpy创建单个字节，然后创建一个数组但没有成功。
我尝试的内容如下：
NSData *d1 =[@"64" dataUsingEncoding:NSUTF16StringEncoding];
NSData *d2 = [@"37" dataUsingEncoding:NSUTF16StringEncoding];
NSData *d3 = [@"81" dataUsingEncoding:NSUTF16StringEncoding];
NSData *d4 = [@"d4" dataUsingEncoding:NSUTF16StringEncoding];
unsigned char *buffer = (unsigned char*)malloc(8);
buffer[0] = [d1 bytes] ;
buffer[1] = [d2 bytes] ;
buffer[2] = [d3 bytes] ;
buffer[3] = [d4 bytes] ;
NSData *data = [NSData dataWithBytes:buffer length:4];
NSString *str = [self encodeBase64WithData:data];
free(buffer);
这导致 IJCgkA== ，而.NET中的代码返回 ZDeB1A==
请注意，转换是针对arrLicence的前四个字节，输入为64,37,81，d4
答案 0 :(得分：4)
尝试这个，我希望这肯定会帮助你。 get-base64-nsstring-from-nsdata
答案 1 :(得分：4)
unsigned char *buffer = (unsigned char*)malloc(8);
buffer[0] = [d1 bytes] ;
buffer[1] = [d2 bytes] ;
buffer[2] = [d3 bytes] ;
buffer[3] = [d4 bytes] ;
不确定您的期望。 bytes返回一个数组，并将数组的地址分配给缓冲区的char元素。此缓冲区不会填充您期望的任何数据，而来自d2的“数据”将部分覆盖来自d1等的数据。
此外，您不应该对字节数组的长度做出太多假设，尤其是在使用UTF-16时。
总之：您不会在转换例程中抛出预期的数据。也许在调试器中检查一下。
答案 2 :(得分：3)
答案 3 :(得分：2)
//strBusiCode = @"64-37-81-d4-39-6d";
NSArray *tmp_arr = [strBusiCode componentsSeparatedByString:@"-"];
NSMutableData *commandToSend= [[NSMutableData alloc] init];
unsigned char whole_byte;
char byte_chars[3] = {'\0','\0','\0'};
int i;
for (i=0; i < [tmp_arr count]; i++) {
byte_chars[0] = [[tmp_arr objectAtIndex:i] characterAtIndex:0];
byte_chars[1] = [[tmp_arr objectAtIndex:i] characterAtIndex:1];
whole_byte = strtol(byte_chars, NULL, 16);
[commandToSend appendBytes:&whole_byte length:1];
}
return commandToSend;
然后将此commandToSend转换为base64数据。
答案 4 :(得分：0)
您可以使用此base64.h和base64.m类解码为base64字符串。
<强> base64.h
#import <Foundation/Foundation.h>
@interface NSData (Base64)
+ (NSData *)dataWithBase64EncodedString:(NSString *)string;
- (id)initWithBase64EncodedString:(NSString *)string;
- (NSString *) base64Encoding;
- (NSString *) base64EncodingWithLineLength:(unsigned int) lineLength;
@end
<强> base64.m
#import "base64.h"
static char encodingTable[64] = {
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P',
'Q','R','S','T','U','V','W','X','Y','Z','a','b','c','d','e','f',
'g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v',
'w','x','y','z','0','1','2','3','4','5','6','7','8','9','+','/' };
@implementation NSData (VQBase64)
- (id)initWithString:(NSString *)string {
if (self = [super init]) {
[self initWithBase64EncodedString:string];
}
return self;
}
+ (NSData *) dataWithBase64EncodedString:(NSString *) string {
return [[[NSData allocWithZone:nil] initWithBase64EncodedString:string] autorelease];
}
- (id) initWithBase64EncodedString:(NSString *) string {
NSMutableData *mutableData = nil;
if( string ) {
unsigned long ixtext = 0;
unsigned long lentext = 0;
unsigned char ch = 0;
unsigned char inbuf[4], outbuf[3];
short i = 0, ixinbuf = 0;
BOOL flignore = NO;
BOOL flendtext = NO;
NSData *base64Data = nil;
const unsigned char *base64Bytes = nil;
// Convert the string to ASCII data.
base64Data = [string dataUsingEncoding:NSASCIIStringEncoding];
base64Bytes = [base64Data bytes];
mutableData = [NSMutableData dataWithCapacity:[base64Data length]];
lentext = [base64Data length];
while( YES ) {
if( ixtext >= lentext ) break;
ch = base64Bytes[ixtext++];
flignore = NO;
if( ( ch >= 'A' ) && ( ch <= 'Z' ) ) ch = ch - 'A';
else if( ( ch >= 'a' ) && ( ch <= 'z' ) ) ch = ch - 'a' + 26;
else if( ( ch >= '0' ) && ( ch <= '9' ) ) ch = ch - '0' + 52;
else if( ch == '+' ) ch = 62;
else if( ch == '=' ) flendtext = YES;
else if( ch == '/' ) ch = 63;
else flignore = YES;
if( ! flignore ) {
short ctcharsinbuf = 3;
BOOL flbreak = NO;
if( flendtext ) {
if( ! ixinbuf ) break;
if( ( ixinbuf == 1 ) || ( ixinbuf == 2 ) ) ctcharsinbuf = 1;
else ctcharsinbuf = 2;
ixinbuf = 3;
flbreak = YES;
}
inbuf [ixinbuf++] = ch;
if( ixinbuf == 4 ) {
ixinbuf = 0;
outbuf [0] = ( inbuf[0] << 2 ) | ( ( inbuf[1] & 0x30) >> 4 );
outbuf [1] = ( ( inbuf[1] & 0x0F ) << 4 ) | ( ( inbuf[2] & 0x3C ) >> 2 );
outbuf [2] = ( ( inbuf[2] & 0x03 ) << 6 ) | ( inbuf[3] & 0x3F );
for( i = 0; i < ctcharsinbuf; i++ )
[mutableData appendBytes:&outbuf[i] length:1];
}
if( flbreak ) break;
}
}
}
self = [self initWithData:mutableData];
return self;
}
- (NSString *) base64Encoding {
return [self base64EncodingWithLineLength:0];
}
- (NSString *) base64EncodingWithLineLength:(unsigned int) lineLength {
const unsigned char *bytes = [self bytes];
NSMutableString *result = [NSMutableString stringWithCapacity:[self length]];
unsigned long ixtext = 0;
unsigned long lentext = [self length];
long ctremaining = 0;
unsigned char inbuf[3], outbuf[4];
unsigned short i = 0;
unsigned short charsonline = 0, ctcopy = 0;
unsigned long ix = 0;
while( YES ) {
ctremaining = lentext - ixtext;
if( ctremaining <= 0 ) break;
for( i = 0; i < 3; i++ ) {
ix = ixtext + i;
if( ix < lentext ) inbuf[i] = bytes[ix];
else inbuf [i] = 0;
}
outbuf [0] = (inbuf [0] & 0xFC) >> 2;
outbuf [1] = ((inbuf [0] & 0x03) << 4) | ((inbuf [1] & 0xF0) >> 4);
outbuf [2] = ((inbuf [1] & 0x0F) << 2) | ((inbuf [2] & 0xC0) >> 6);
outbuf [3] = inbuf [2] & 0x3F;
ctcopy = 4;
switch( ctremaining ) {
case 1:
ctcopy = 2;
break;
case 2:
ctcopy = 3;
break;
}
for( i = 0; i < ctcopy; i++ )
[result appendFormat:@"%c", encodingTable[outbuf[i]]];
for( i = ctcopy; i < 4; i++ )
[result appendString:@"="];
ixtext += 3;
charsonline += 4;
if( lineLength > 0 ) {
if( charsonline >= lineLength ) {
charsonline = 0;
[result appendString:@"\n"];
}
}
}
return [NSString stringWithString:result];
}
@end
请检查并告知我是否有任何问题。
答案 5 :(得分：0)
如果你看一下你给出的最后两个数字作为例子，你会注意到转换匹配。因为hi和low部分是相同的。
只需交换高低字。