本文基本全部都是代码
首先是.H文件
1 #import <Foundation/Foundation.h> 2 3 @interface Base64AndImageHelp : NSObject 4 - (NSString*)encodeURL:(NSString *)string; 5 +(id)mydataWithBase64EncodedString:(NSString *)string ; 6 @end
然后是.M文件
1 #import "Base64AndImageHelp.h" 2 @interface NSData (MBBase64) 3 4 + (id)dataWithBase64EncodedString:(NSString *)string; 5 - (NSString *)base64Encoding; 6 7 @end 8 static const char encodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 9 10 @implementation NSData (MBBase64) 11 12 + (id)dataWithBase64EncodedString:(NSString *)string { 13 if (string == nil) 14 [NSException raise:NSInvalidArgumentException format:@""]; 15 16 if ([string length] == 0) 17 return [NSData data]; 18 19 static char *decodingTable = NULL; 20 21 if (decodingTable == NULL) { 22 decodingTable = malloc(256); 23 if (decodingTable == NULL) 24 return nil; 25 memset(decodingTable, CHAR_MAX, 256); 26 NSUInteger i; 27 for (i = 0; i < 64; i++) 28 decodingTable[(short)encodingTable[i]] = i; 29 } 30 31 const char *characters = [string cStringUsingEncoding:NSASCIIStringEncoding]; 32 if (characters == NULL) 33 return nil; 34 char *bytes = malloc((([string length] + 3) / 4) * 3); 35 if (bytes == NULL) 36 return nil; 37 38 NSUInteger length = 0; 39 NSUInteger i = 0; 40 41 while (YES) { 42 char buffer[4]; 43 short bufferLength; 44 for (bufferLength = 0; bufferLength < 4; i++) { 45 if (characters[i] == '\0') 46 break; 47 if (isspace(characters[i]) || characters[i] == '=') 48 continue; 49 buffer[bufferLength] = decodingTable[(short)characters[i]]; 50 if (buffer[bufferLength++] == CHAR_MAX) { 51 free(bytes); 52 return nil; 53 } 54 } 55 56 if (bufferLength == 0) 57 break; 58 if (bufferLength == 1) { 59 free(bytes); 60 return nil; 61 } 62 63 bytes[length++] = (buffer[0] << 2) | (buffer[1] >> 4); 64 if (bufferLength > 2) 65 bytes[length++] = (buffer[1] << 4) | (buffer[2] >> 2); 66 if (bufferLength > 3) 67 bytes[length++] = (buffer[2] << 6) | buffer[3]; 68 } 69 70 realloc(bytes, length); 71 return [NSData dataWithBytesNoCopy:bytes length:length]; 72 } 73 74 - (NSString *)base64Encoding { 75 if ([self length] == 0) 76 return @""; 77 78 char *characters = malloc((([self length] + 2) / 3) * 4); 79 if (characters == NULL) 80 return nil; 81 82 NSUInteger length = 0; 83 NSUInteger i = 0; 84 85 while (i < [self length]) { 86 char buffer[3] = {0,0,0}; 87 short bufferLength = 0; 88 while (bufferLength < 3 && i < [self length]) 89 buffer[bufferLength++] = ((char *)[self bytes])[i++]; 90 characters[length++] = encodingTable[(buffer[0] & 0xFC) >> 2]; 91 characters[length++] = encodingTable[((buffer[0] & 0x03) << 4) | ((buffer[1] & 0xF0) >> 4)]; 92 if (bufferLength > 1) 93 characters[length++] = encodingTable[((buffer[1] & 0x0F) << 2) | ((buffer[2] & 0xC0) >> 6)]; 94 else characters[length++] = '='; 95 if (bufferLength > 2) 96 characters[length++] = encodingTable[buffer[2] & 0x3F]; 97 else characters[length++] = '='; 98 } 99 100 return [[NSString alloc] initWithBytesNoCopy:characters length:length encoding:NSASCIIStringEncoding freeWhenDone:YES] ; 101 } 102 103 @end 104 @implementation Base64AndImageHelp 105 - (NSString*)encodeURL:(NSString *)string 106 { 107 NSString *newString = (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes( kCFAllocatorDefault, (CFStringRef)string, NULL, CFSTR(":/?#[]@!$ &'()*+,;=\"<>%{}|\\^~`"),kCFStringEncodingUTF8)); 108 if (newString) { 109 return newString; 110 } 111 return @""; 112 113 114 } 115 + (id)mydataWithBase64EncodedString:(NSString *)string { 116 if (string == nil) 117 [NSException raise:NSInvalidArgumentException format:@""]; 118 119 if ([string length] == 0) 120 return [NSData data]; 121 122 static char *decodingTable = NULL; 123 124 if (decodingTable == NULL) { 125 decodingTable = malloc(256); 126 if (decodingTable == NULL) 127 return nil; 128 memset(decodingTable, CHAR_MAX, 256); 129 NSUInteger i; 130 for (i = 0; i < 64; i++) 131 decodingTable[(short)encodingTable[i]] = i; 132 } 133 134 const char *characters = [string cStringUsingEncoding:NSASCIIStringEncoding]; 135 if (characters == NULL) 136 return nil; 137 char *bytes = malloc((([string length] + 3) / 4) * 3); 138 if (bytes == NULL) 139 return nil; 140 141 NSUInteger length = 0; 142 NSUInteger i = 0; 143 144 while (YES) { 145 char buffer[4]; 146 short bufferLength; 147 for (bufferLength = 0; bufferLength < 4; i++) { 148 if (characters[i] == '\0') 149 break; 150 if (isspace(characters[i]) || characters[i] == '=') 151 continue; 152 buffer[bufferLength] = decodingTable[(short)characters[i]]; 153 if (buffer[bufferLength++] == CHAR_MAX) { 154 free(bytes); 155 return nil; 156 } 157 } 158 159 if (bufferLength == 0) 160 break; 161 if (bufferLength == 1) { 162 free(bytes); 163 return nil; 164 } 165 166 bytes[length++] = (buffer[0] << 2) | (buffer[1] >> 4); 167 if (bufferLength > 2) 168 bytes[length++] = (buffer[1] << 4) | (buffer[2] >> 2); 169 if (bufferLength > 3) 170 bytes[length++] = (buffer[2] << 6) | buffer[3]; 171 } 172 173 realloc(bytes, length); 174 return [NSData dataWithBytesNoCopy:bytes length:length]; 175 } 176 @end
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