c# - c# winrt删除文件

Question

当我删除这样的文件时，它会引发异常：

值不在预期范围内。

当deleteasync.

public static async Task DeleteFile(string fileName, string folderPath)
    {
        try
        {
            StorageFolder sf = await CheckFolder(folderPath);
            StorageFile sfile = await sf.GetFileAsync(fileName);
            if (sfile != null)
            {
                await sfile.DeleteAsync();
            }
        }
        catch (Exception)
        {

        }
    }