IOS开发---菜鸟学习之路--（十四）-将BASE64图片转换成Image

本文基本全部都是代码

首先是.H文件

 #import <Foundation/Foundation.h>

 @interface Base64AndImageHelp : NSObject
 - (NSString*)encodeURL:(NSString *)string;
 +(id)mydataWithBase64EncodedString:(NSString *)string ;
 @end

Base64AndImageHelp.h

然后是.M文件

 #import "Base64AndImageHelp.h"
 @interface NSData (MBBase64)

 + (id)dataWithBase64EncodedString:(NSString *)string;
 - (NSString *)base64Encoding;

 @end
 static const char encodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

 @implementation NSData (MBBase64)

 + (id)dataWithBase64EncodedString:(NSString *)string {
     if (string == nil)
         [NSException raise:NSInvalidArgumentException format:@""];

     if ([string length] == )
         return [NSData data];

     static char *decodingTable = NULL;

     if (decodingTable == NULL) {
         decodingTable = malloc();
         if (decodingTable == NULL)
             return nil;
         memset(decodingTable, CHAR_MAX, );
         NSUInteger i;
         for (i = ; i < ; i++)
             decodingTable[(short)encodingTable[i]] = i;
     }

     const char *characters = [string cStringUsingEncoding:NSASCIIStringEncoding];
     if (characters == NULL)
         return nil;
     char *bytes = malloc((([string length] + ) / ) * );
     if (bytes == NULL)
         return nil;

     NSUInteger length = ;
     NSUInteger i = ;

     while (YES) {
         char buffer[];
         short bufferLength;
         for (bufferLength = ; bufferLength < ; i++) {
             if (characters[i] == '\0')
                 break;
             if (isspace(characters[i]) || characters[i] == '=')
                 continue;
             buffer[bufferLength] = decodingTable[(short)characters[i]];
             if (buffer[bufferLength++] == CHAR_MAX) {
                 free(bytes);
                 return nil;
             }
         }

         if (bufferLength == )
             break;
         if (bufferLength == ) {
             free(bytes);
             return nil;
         }

         bytes[length++] = (buffer[] << ) | (buffer[] >> );
         if (bufferLength > )
             bytes[length++] = (buffer[] << ) | (buffer[] >> );
         if (bufferLength > )
             bytes[length++] = (buffer[] << ) | buffer[];
     }

     realloc(bytes, length);
     return [NSData dataWithBytesNoCopy:bytes length:length];
 }

 - (NSString *)base64Encoding {
     if ([self length] == )
         return @"";

     char *characters = malloc((([self length] + ) / ) * );
     if (characters == NULL)
         return nil;

     NSUInteger length = ;
     NSUInteger i = ;

     while (i < [self length]) {
         char buffer[] = {,,};
         short bufferLength = ;
         while (bufferLength <  && i < [self length])
             buffer[bufferLength++] = ((char *)[self bytes])[i++];
         characters[length++] = encodingTable[(buffer[] & 0xFC) >> ];
         characters[length++] = encodingTable[((buffer[] & 0x03) << ) | ((buffer[] & 0xF0) >> )];
         if (bufferLength > )
             characters[length++] = encodingTable[((buffer[] & 0x0F) << ) | ((buffer[] & 0xC0) >> )];
         else characters[length++] = '=';
         if (bufferLength > )
             characters[length++] = encodingTable[buffer[] & 0x3F];
         else characters[length++] = '=';
     }

     return [[NSString alloc] initWithBytesNoCopy:characters length:length encoding:NSASCIIStringEncoding freeWhenDone:YES] ;
 }

 @end
 @implementation Base64AndImageHelp
 - (NSString*)encodeURL:(NSString *)string
 {
     NSString *newString = (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes( kCFAllocatorDefault, (CFStringRef)string, NULL, CFSTR(":/?#[]@!$ &'()*+,;=\"<>%{}|\\^~`"),kCFStringEncodingUTF8));
     if (newString) {
         return newString;
     }
     return @"";

 }
 + (id)mydataWithBase64EncodedString:(NSString *)string {
     if (string == nil)
         [NSException raise:NSInvalidArgumentException format:@""];

     if ([string length] == )
         return [NSData data];

     static char *decodingTable = NULL;

     if (decodingTable == NULL) {
         decodingTable = malloc();
         if (decodingTable == NULL)
             return nil;
         memset(decodingTable, CHAR_MAX, );
         NSUInteger i;
         for (i = ; i < ; i++)
             decodingTable[(short)encodingTable[i]] = i;
     }

     const char *characters = [string cStringUsingEncoding:NSASCIIStringEncoding];
     if (characters == NULL)
         return nil;
     char *bytes = malloc((([string length] + ) / ) * );
     if (bytes == NULL)
         return nil;

     NSUInteger length = ;
     NSUInteger i = ;

     while (YES) {
         char buffer[];
         short bufferLength;
         for (bufferLength = ; bufferLength < ; i++) {
             if (characters[i] == '\0')
                 break;
             if (isspace(characters[i]) || characters[i] == '=')
                 continue;
             buffer[bufferLength] = decodingTable[(short)characters[i]];
             if (buffer[bufferLength++] == CHAR_MAX) {
                 free(bytes);
                 return nil;
             }
         }

         if (bufferLength == )
             break;
         if (bufferLength == ) {
             free(bytes);
             return nil;
         }

         bytes[length++] = (buffer[] << ) | (buffer[] >> );
         if (bufferLength > )
             bytes[length++] = (buffer[] << ) | (buffer[] >> );
         if (bufferLength > )
             bytes[length++] = (buffer[] << ) | buffer[];
     }

     realloc(bytes, length);
     return [NSData dataWithBytesNoCopy:bytes length:length];
 }
 @end

Base64AndImageHelp.m

完成该类后就可以在其他类中使用了

NSData *newimage=[Base64AndImageHelp mydataWithBase64EncodedString:base64的STRING];

UIImage *newjiaban=[[UIImage alloc] initWithData:newimage];

ok这样就完成拉