iOS本地圖片緩存無法加載解決辦法

最近做了一個功能，把圖片緩存到App中。保存成功後，通過地址加載圖片，發現可以成功。

但是關閉程序後，再次啓動，發現直接通過保存的地址加載圖片總是失敗。

解決方法：獲取圖片時，需要重新拼接圖片路徑，就可以加載成功了。

 

保存圖片代碼：

+ (NSString *)saveImage:(UIImage *)image imageName:(NSString *)imageName
{
    
    NSData *imageData = UIImageJPEGRepresentation(image, 0.3);
    
    BOOL success;
    
    NSError *error;
    
    NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
    
    NSString *documentsDirectory = [paths objectAtIndex:0];
    
    NSString *imgCachePath = @"img-cache";
    
    NSString *imgCacheAbsolutePath = [NSString stringWithFormat:@"%@/html-resources/%@",documentsDirectory,imgCachePath];
    
    NSFileManager *fileManager = [NSFileManager defaultManager];
    
    //判斷是否存在改文件夾，不存在創建
    success = [fileManager fileExistsAtPath:imgCacheAbsolutePath];
    
    if(!success) {
        
        [fileManager createDirectoryAtPath:imgCacheAbsolutePath withIntermediateDirectories:YES attributes:nil error:&error];
        
    }
    
    // 圖片名
    NSString *imgPath = [NSString stringWithFormat:@"%@/%@.jpg",imgCachePath,imageName];
    NSString *imgAbsolutePath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"/html-resources/%@", imgPath]];
    [imageData writeToFile:imgAbsolutePath atomically:YES];
    return imageName;
}

 

加載圖片代碼

- (UIImage *)getSaveImage:(NSString *)imageName
{
    NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
       
    NSString *imgCachePath = @"img-cache";
       
    NSString *imgPath = [NSString stringWithFormat:@"%@/%@.jpg",imgCachePath,imageName];
    NSString *imgAbsolutePath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"/html-resources/%@", imgPath]];
    
    return [UIImage imageWithContentsOfFile:imgAbsolutePath];
}