ios - The difference between captureImage.image; and [captureImage].image; -

i trying use captureimage.image; in code can explain code mean , correct captureimage.image; or [captureimage].image; or [captureimage.image];

i using code .h

    iboutlet uipickerview     *savetopicker;     nsmutablearray            *arraygenre; }  @property(nonatomic, retain) avcapturestillimageoutput *stillimageoutput; @property (weak, nonatomic) iboutlet uilabel *categorylabel;  @property (weak, nonatomic) iboutlet uiview *imagepreview; @property (weak, nonatomic) iboutlet uiview *saveimage; @property (weak, nonatomic) iboutlet uiimageview *captureimage; @property (weak, nonatomic) iboutlet uisegmentedcontrol *cameraswitch; @property (weak, nonatomic) iboutlet uiview *pickerviewcontainer;  @property (nonatomic, retain) uiaccelerometer *accelerometer; @property (weak,nonatomic) iboutlet uiscrollview *bgscrollview; - (ibaction)savebutton:(id)sender; - (ibaction)closebutton:(id)sender;    - (ibaction)switchcamera:(id)sender; - (ibaction)snapimage:(id)sender; 

for implementation file

  - (void)pickerview:(uipickerview *)pickerview didselectrow:(nsinteger)row incomponent:(nsinteger)component{         nsarray  *paths = nssearchpathfordirectoriesindomains(nsdocumentdirectory, nsuserdomainmask, yes);         nsstring *documentsdirectory = [paths objectatindex:0];         //fetch category name array used fill picker view         nsstring *categoryname= [arraygenre objectatindex:row];         nsstring *fpath = [documentsdirectory stringbyappendingpathcomponent:categoryname];         nsfilemanager *filemanager=[[nsfilemanager alloc]init];         [filemanager createdirectoryatpath:fpath withintermediatedirectories:yes attributes:nil error:nil];          [captureimage.image];         [data writetofile:fpath atomically:yes];         nsdata *data= uiimagepngrepresentation(image);      } - (ibaction)snapimage:(id)sender {     if (!haveimage) {         captureimage.image = nil; //remove old image view         captureimage.hidden = no; //show captured image view         imagepreview.hidden = yes; //hide live video feed         [self capimage];     }     else {         captureimage.hidden = yes;         imagepreview.hidden = no;         haveimage = no;     } }  - (void) capimage { //method capture image avcapturesession video feed     avcaptureconnection *videoconnection = nil;     (avcaptureconnection *connection in stillimageoutput.connections) {          (avcaptureinputport *port in [connection inputports]) {              if ([[port mediatype] isequal:avmediatypevideo] ) {                 videoconnection = connection;                 break;             }         }          if (videoconnection) {             break;         }     }      nslog(@"about request capture from: %@", stillimageoutput);     [stillimageoutput capturestillimageasynchronouslyfromconnection:videoconnection completionhandler: ^(cmsamplebufferref imagesamplebuffer, nserror *error) {          if (imagesamplebuffer != null) {             nsdata *imagedata = [avcapturestillimageoutput jpegstillimagensdatarepresentation:imagesamplebuffer];             [self processimage:[uiimage imagewithdata:imagedata]];         }     }]; }   - (void) processimage:(uiimage *)image { //process captured image, crop, resize , rotate     haveimage = yes;      if([uidevice currentdevice].userinterfaceidiom==uiuserinterfaceidiompad) { //device ipad         // resize image         uigraphicsbeginimagecontext(cgsizemake(768, 1022));         [image drawinrect: cgrectmake(0, 0, 768, 1022)];         uiimage *smallimage = uigraphicsgetimagefromcurrentimagecontext();         uigraphicsendimagecontext();          cgrect croprect = cgrectmake(0, 130, 768, 768);         cgimageref imageref = cgimagecreatewithimageinrect([smallimage cgimage], croprect);         //or use uiimage wherever          [captureimage setimage:[uiimage imagewithcgimage:imageref]];          cgimagerelease(imageref);         captureimage.hidden = no;      }else{ //device iphone         // resize image         uigraphicsbeginimagecontext(cgsizemake(320, 426));         [image drawinrect: cgrectmake(0, 0, 320, 426)];         uiimage *smallimage = uigraphicsgetimagefromcurrentimagecontext();         uigraphicsendimagecontext();          cgrect croprect = cgrectmake(0, 55, 320, 320);         cgimageref imageref = cgimagecreatewithimageinrect([smallimage cgimage], croprect);          [captureimage setimage:[uiimage imagewithcgimage:imageref]];          cgimagerelease(imageref);     }       //adjust image orientation based on device orientation     if ([[uidevice currentdevice] orientation] == uideviceorientationlandscapeleft) {         nslog(@"landscape left image");          [uiview beginanimations:@"rotate" context:nil];         [uiview setanimationduration:0.5];         captureimage.transform = cgaffinetransformmakerotation(degreestoradians(-90));         [uiview commitanimations];      }     if ([[uidevice currentdevice] orientation] == uideviceorientationlandscaperight) {         nslog(@"landscape right");          [uiview beginanimations:@"rotate" context:nil];         [uiview setanimationduration:0.5];         captureimage.transform = cgaffinetransformmakerotation(degreestoradians(90));         [uiview commitanimations];      }     if ([[uidevice currentdevice] orientation] == uideviceorientationportraitupsidedown) {         nslog(@"upside down");         [uiview beginanimations:@"rotate" context:nil];         [uiview setanimationduration:0.5];         captureimage.transform = cgaffinetransformmakerotation(degreestoradians(180));         [uiview commitanimations];      }     if ([[uidevice currentdevice] orientation] == uideviceorientationportrait) {         nslog(@"upside upright");         [uiview beginanimations:@"rotate" context:nil];         [uiview setanimationduration:0.5];         captureimage.transform = cgaffinetransformmakerotation(degreestoradians(0));         [uiview commitanimations];     } } 

however getting errors saying expected identifier on first captureimage.image code , use of undeclared identifier data on the[data writetofile:fpath atomically:yes];and use of undeclared identifier image in nsdata *data= uiimagepngrepresentation(image);

did wrong?

you give more information on you're trying achieve, , isn't working. answer question: captureimage.image 1 valid syntax of three

edit: see you've updated answer code, it's not clear me captureimage line should do. captureimage.image calls image method (usually property) on captureimage object, there's no declaration object.

edit 2: assuming captureimage exists outside of method, last few lines should this:

uiimage *image = captureimage.image; nsdata *data = uiimagepngrepresentation(image); [data writetofile:fpath atomically:yes];