Unicode轉化為漢字:

+ (NSString *)replaceUnicode:(NSString *)unicodeStr {  
    
   NSString *tempStr1 = [unicodeStrstringByReplacingOccurrencesOfString:@"\\u"withString:@"\\U"];  
   NSString *tempStr2 = [tempStr1stringByReplacingOccurrencesOfString:@"\""withString:@"\\\""];  
   NSString *tempStr3 = [[@"\""stringByAppendingString:tempStr2]stringByAppendingString:@"\""];  
   NSData *tempData = [tempStr3dataUsingEncoding:NSUTF8StringEncoding];  
   NSString* returnStr = [NSPropertyListSerializationpropertyListFromData:tempData  
                                                          mutabilityOption:NSPropertyListImmutable   
                                                                    format:NULL  
                                                          errorDescription:NULL];  
    
   return [returnStrstringByReplacingOccurrencesOfString:@"\\r\\n"withString:@"\n"];     
}

漢字與utf8相互轉化:

NSString* strA = [@"%E4%B8%AD%E5%9B%BD"stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSString *strB = [@"中國"stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

NSString 轉化為utf8:

NSString *strings = [NSStringstringWithFormat:@"abc"];
    
    NSLog(@"strings : %@",strings);
    
   CF_EXPORT
    CFStringRef CFURLCreateStringByAddingPercentEscapes(CFAllocatorRef allocator,CFStringReforiginalString,CFStringRef charactersToLeaved, CFStringReflegalURLCharactersToBeEscaped,CFStringEncoding encoding);
    
    NSString *encodedValue = (__bridge NSString*)CFURLCreateStringByAddingPercentEscapes(nil,(__bridgeCFStringRef)strings,nil, (CFStringRef)@"!*'();:@&=+$,/?%#[]",kCFStringEncodingUTF8);

iso8859－1 到 unicode編碼轉換:

+ (NSString *)changeISO88591StringToUnicodeString:(NSString *)iso88591String
{
    
    NSMutableString *srcString = [[[NSMutableString alloc]initWithString:iso88591String]autorelease];
    
    [srcString replaceOccurrencesOfString:@"&" withString:@"&" options:NSLiteralSearchrange:NSMakeRange(0, [srcString length])];
    [srcString replaceOccurrencesOfString:@"&#x" withString:@"" options:NSLiteralSearchrange:NSMakeRange(0, [srcString length])];
        
    NSMutableString *desString = [[[NSMutableString alloc]init] autorelease];
    
    NSArray *arr = [srcString componentsSeparatedByString:@";"];
    
    for(int i=0;i<[arr count]-1;i++){
        
        NSString *v = [arr objectAtIndex:i];
        char *c = malloc(3);
        int value = [StringUtil changeHexStringToDecimal:v];
        c[1] = value  &0x00FF;
        c[0] = value >>8 &0x00FF;
        c[2] = '\0';
        [desString appendString:[NSString stringWithCString:c encoding:NSUnicodeStringEncoding]];
        free(c);
    }
    
    return desString;
}