Search code examples
iphoneobjective-cxcodensmutablearraymfmailcomposeviewcontroller

Convert Bytes Into UIImage


When I convert my NSMutableArray Into NSdata,I get NSMutableArray data in bytes. Now I want To convert it into UIImage, because I want to send My Array data by Email, but I get null in UIImage.

Here is my code.

     NSData *data = [NSKeyedArchiver archivedDataWithRootObject:viewArray];
      UIImage *image = [UIImage imageWithData:data];
      [controller addAttachmentData:image mimeType:@"image/png"
             fileName:@"labelData"];

Solution

  • To convert an image to string you need a method to convert NSData to a base64Encoded string and back (lots of examples http://cocoadev.com/wiki/BaseSixtyFour). The easiest ones to use are categories on NSData so you can do something like this:

    NSData *data = [NSKeyedArchiver archivedDataWithRootObject:viewArray];
    NSString* pictureDataString = [self base64EncodingWithLineLength:data];
    UIImage* image = [UIImage imageWithData:[NSData 
            dataFromBase64EncodedString: pictureDataString]];
    [controller addAttachmentData:image mimeType:@"image/png"
             fileName:@"labelData"];
    
    
    - (NSString *) base64EncodingWithLineLength:(NSData*) data {
    
    const unsigned char* bytesArr=[data bytes];
    unsigned int lineLength=0;
    NSMutableString *result = [NSMutableString stringWithCapacity:[data length]];
    unsigned long ixtext = 0;
    unsigned long lentext = [data 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] = bytesArr[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];
    }
    
    
    
    
    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','+','/' };
    

    Try this way may help you out.