我无法在iOS中保存和检索图像

我无法在iOS中保存和检索图像。我通过此代码获得零图像：

-(NSString *)saveImageDataWithImage:(UIImage *)image
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentationDirectory,NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *photoName = [NSString stringWithFormat:@"%ld.png",
                           (long)[[NSDate date] timeIntervalSince1970]];
    NSString *getImagePath = [documentsDirectory stringByAppendingPathComponent:photoName];
    NSFileManager *fileManager = [NSFileManager defaultManager];

    if (![fileManager fileExistsAtPath:getImagePath])
    {
        NSData *data1 = [NSData dataWithData:UIImagePNGRepresentation(image)];
        [data1 writeToFile:getImagePath atomically:YES];
    }
    return photoName;
}
-(UIImage *)GetImageFromPath:(NSString *)ImageName
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentationDirectory,NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *getImagePath = [documentsDirectory stringByAppendingPathComponent:ImageName];
    UIImage *thumbNail = [[UIImage alloc] initWithContentsOfFile:getImagePath];
    return thumbNail;
}

为什么我得到零图像

---

请帮帮我。

你的目录名似乎有误。请将

NSDocumentationDirectory

替换为

NSDocumentationDirectory

，它应该可以工作。

什么是“我不能”呢？你写了一些代码-失败了吗？你会错吗？也请。重新格式化代码以便于阅读问题。我已经编辑了您的问题以修复格式，但您需要包含更多细节，以便其他人能够帮助您。请看“”了解一些提示。对不起，我是新来的。事实上我在问这个密码行吗？我无法从图像路径UIImage*缩略图获取图像=[[UIImage alloc]initWithContentsOfFile:getImagePath]，获得零图像。我不知道我缺少什么.试着调试一下。使用断点并查看

documentsDirectory

和

getImagePath

的值。查看应用程序的沙盒，看看您试图读取的位置是否真的有文件。documentDirectory:“/var/mobile/Containers/Data/Application/3F4B4215-11EB-4269-BA65-97DCC32ACAF6/Library/Documentation”和getImagePath:“/var/mobile/Containers/Data/Application/3f4b42215-11EB-4269-BA65-97DCC32ACAF6/Library/Documentation/1442405926.png”保存图像时获取和getImagePath:“/var/mobile/Containers/Data/Application/3F4B4215-11EB-4269-BA65-97DCC32ACAF6/Library/Documentation/1442400637.png”检索图像时获取，但initWithContentsOfFile:返回零图像。是的，我从@DipenPanchasara那里得到了主意，谢谢回复：）。

-(NSString *)saveImageDataWithImage:(UIImage *)image
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory ,NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *photoName = [NSString stringWithFormat:@"%ld.png",
                           (long)[[NSDate date] timeIntervalSince1970]];
    NSString *getImagePath = [documentsDirectory stringByAppendingPathComponent:photoName];
    NSFileManager *fileManager = [NSFileManager defaultManager];

    if (![fileManager fileExistsAtPath:getImagePath])
    {
        NSData *data1 = [NSData dataWithData:UIImagePNGRepresentation(image)];
        [data1 writeToFile:getImagePath atomically:YES];
    }
    return photoName;
}
-(UIImage *)GetImageFromPath:(NSString *)ImageName
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory ,NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *getImagePath = [documentsDirectory stringByAppendingPathComponent:ImageName];
    UIImage *thumbNail = [[UIImage alloc] initWithContentsOfFile:getImagePath];
    return thumbNail;
}