使用GTMBase64编码解码字符串

GTMDefines.h
GTMBase64.h
GTMBase64.m

你可以在这里找到这三个文件
http://code.google.com/p/google-toolbox-for-mac/source/browse/trunk/Foundation/?r=87

#import "GTMBase64.h"

- (void)testExample
{
NSData *data = [@"HelloWorld" dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
NSString* encoded = [[NSString alloc] initWithData:[GTMBase64 encodeData:data] encoding:NSUTF8StringEncoding];
NSLog(@"encoded:%@", encoded);
NSString* decoded = [[NSString alloc] initWithData:[GTMBase64 decodeString:encoded] encoding:NSUTF8StringEncoding];
NSLog(@"decoded:%@", decoded);
[encoded release];
[decoded release];
}

2012-04-10 12:13:10.121 fs_test[7370:b603] encoded:SGVsbG9Xb3JsZA==
2012-04-10 12:13:10.122 fs_test[7370:b603] decoded:HelloWorld