列表不适用于 GetFiles 方法

Question

Trying to figure out why this isn't working, the list is to retrieve photos using the combobox item (which lists local HDDs root address as items) when selected that item it is converted into a string and supposed to be used as GetFiles 方法的路径但在运行时在 (string path = ) 行上搞砸了，我得到“对象引用未设置为对象的实例”非常感谢如果有人能告诉我出了什么问题

public List<Photos> LoadImages ///List Retrieves and Loads Photos
    {

        get
        {
            List<Photos> Image = new List<Photos>();
            string path = HDDSelectionBox.SelectedItem.ToString(); //ComboBox SelectedItem Converted To String As Path
            foreach (string filename in Directory.GetFiles(path, "*jpg")) 
            {
                try
                {
                    Image.Add( //Add To List
                        new Photos(
                            new BitmapImage(
                                new Uri(filename)),
                                System.IO.Path.GetFileNameWithoutExtension(filename)));
                }
                catch { } //Skips Any Image That Isn't Image/Cant Be Loaded
            }
            return Image;
        }
    }

Answer 1

你应该把.放在文件扩展名之前：

Directory.GetFiles(path, "*.jpg")

你还需要检查HDDSelectionBox.SelectedItem是否不为空：

public List<Photos> LoadImages ///List Retrieves and Loads Photos
{
    get
    {
        List<Photos> images = new List<Photos>();
        if (HDDSelectionBox.SelectedItem != null)
        {
            string path = HDDSelectionBox.SelectedItem.ToString(); //ComboBox SelectedItem Converted To String As Path
            foreach (string filename in Directory.GetFiles(path, "*.jpg"))
            {
                try
                {
                    images.Add( //Add To List
                        new Photos(
                            new BitmapImage(
                                new Uri(filename)),
                                System.IO.Path.GetFileNameWithoutExtension(filename)));
                }
                catch { } //Skips Any Image That Isn't Image/Cant Be Loaded
            }
        }
        return images;
    }
}

此外，这可能更适合于方法而不是属性，因为它会进行大量处理...