在App中存取照片

 1 - (void)setPhoto:(UIImage *)image{
 2     UIImage *image = image;
 3      4
 5     //0.5代表的是压缩率，1为不压缩，图像质量最高，0为最高压缩，图像质量最低
 6     NSData *imageData = UIImageJPEGRepresentation(image, 0.5);
 7     NSString *relativePath = @"UserPhoto.jpg";
 8     NSString *path = [self documentsPathForFileName:relativePath];
 9     NSLog(@"path %@", path);
10     [imageData writeToFile:path atomically:YES];
11     [[NSUserDefaults standardUserDefaults] setObject:path forKey:kUserImagePath];
12     [[NSUserDefaults standardUserDefaults] synchronize];
13 }
14 
15 - (NSString*)documentsPathForFileName:(NSString*)name{
16     NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
17     NSString *documentsPath = [paths objectAtIndex:0];
18     return [documentsPath stringByAppendingPathComponent:name];
19 }

NSString *imagePath = [[NSUserDefaults standardUserDefaults] objectForKey:kUserImagePath];
    if (imagePath) {
       image = [UIImage imageWithData:[NSData dataWithContentsOfFile:imagePath]];
    }