step 1: extend interface Microsoft.Extensions.FileProviders.IFileProvider
public interface INopFileProvider : IFileProvider
public interface INopFileProvider : IFileProvider
{
/// <summary>
/// Combines an array of strings into a path
/// </summary>
/// <param name="paths">An array of parts of the path</param>
/// <returns>The combined paths</returns>
string Combine(params string[] paths);
/// <summary>
/// Creates all directories and subdirectories in the specified path unless they already exist
/// </summary>
/// <param name="path">The directory to create</param>
void CreateDirectory(string path);
/// <summary>
/// Creates or overwrites a file in the specified path
/// </summary>
/// <param name="path">The path and name of the file to create</param>
void CreateFile(string path);
/// <summary>
/// Depth-first recursive delete, with handling for descendant directories open in Windows Explorer.
/// </summary>
/// <param name="path">Directory path</param>
void DeleteDirectory(string path);
/// <summary>
/// Deletes the specified file
/// </summary>
/// <param name="filePath">The name of the file to be deleted. Wildcard characters are not supported</param>
void DeleteFile(string filePath);
/// <summary>
/// Determines whether the given path refers to an existing directory on disk
/// </summary>
/// <param name="path">The path to test</param>
/// <returns>
/// true if path refers to an existing directory; false if the directory does not exist or an error occurs when
/// trying to determine if the specified file exists
/// </returns>
bool DirectoryExists(string path);
/// <summary>
/// Moves a file or a directory and its contents to a new location
/// </summary>
/// <param name="sourceDirName">The path of the file or directory to move</param>
/// <param name="destDirName">
/// The path to the new location for sourceDirName. If sourceDirName is a file, then destDirName
/// must also be a file name
/// </param>
void DirectoryMove(string sourceDirName, string destDirName);
/// <summary>
/// Returns an enumerable collection of file names that match a search pattern in
/// a specified path, and optionally searches subdirectories.
/// </summary>
/// <param name="directoryPath">The path to the directory to search</param>
/// <param name="searchPattern">
/// The search string to match against the names of files in path. This parameter
/// can contain a combination of valid literal path and wildcard (* and ?) characters
/// , but doesn't support regular expressions.
/// </param>
/// <param name="topDirectoryOnly">
/// Specifies whether to search the current directory, or the current directory and all
/// subdirectories
/// </param>
/// <returns>
/// An enumerable collection of the full names (including paths) for the files in
/// the directory specified by path and that match the specified search pattern
/// </returns>
IEnumerable<string> EnumerateFiles(string directoryPath, string searchPattern, bool topDirectoryOnly = true);
/// <summary>
/// Copies an existing file to a new file. Overwriting a file of the same name is allowed
/// </summary>
/// <param name="sourceFileName">The file to copy</param>
/// <param name="destFileName">The name of the destination file. This cannot be a directory</param>
/// <param name="overwrite">true if the destination file can be overwritten; otherwise, false</param>
void FileCopy(string sourceFileName, string destFileName, bool overwrite = false);
/// <summary>
/// Determines whether the specified file exists
/// </summary>
/// <param name="filePath">The file to check</param>
/// <returns>
/// True if the caller has the required permissions and path contains the name of an existing file; otherwise,
/// false.
/// </returns>
bool FileExists(string filePath);
/// <summary>
/// Gets the length of the file in bytes, or -1 for a directory or non-existing files
/// </summary>
/// <param name="path">File path</param>
/// <returns>The length of the file</returns>
long FileLength(string path);
/// <summary>
/// Moves a specified file to a new location, providing the option to specify a new file name
/// </summary>
/// <param name="sourceFileName">The name of the file to move. Can include a relative or absolute path</param>
/// <param name="destFileName">The new path and name for the file</param>
void FileMove(string sourceFileName, string destFileName);
/// <summary>
/// Returns the absolute path to the directory
/// </summary>
/// <param name="paths">An array of parts of the path</param>
/// <returns>The absolute path to the directory</returns>
string GetAbsolutePath(params string[] paths);
/// <summary>
/// Gets a System.Security.AccessControl.DirectorySecurity object that encapsulates the access control list (ACL) entries for a specified directory
/// </summary>
/// <param name="path">The path to a directory containing a System.Security.AccessControl.DirectorySecurity object that describes the file's access control list (ACL) information</param>
/// <returns>An object that encapsulates the access control rules for the file described by the path parameter</returns>
DirectorySecurity GetAccessControl(string path);
/// <summary>
/// Returns the creation date and time of the specified file or directory
/// </summary>
/// <param name="path">The file or directory for which to obtain creation date and time information</param>
/// <returns>
/// A System.DateTime structure set to the creation date and time for the specified file or directory. This value
/// is expressed in local time
/// </returns>
DateTime GetCreationTime(string path);
/// <summary>
/// Returns the names of the subdirectories (including their paths) that match the
/// specified search pattern in the specified directory
/// </summary>
/// <param name="path">The path to the directory to search</param>
/// <param name="searchPattern">
/// The search string to match against the names of subdirectories in path. This
/// parameter can contain a combination of valid literal and wildcard characters
/// , but doesn't support regular expressions.
/// </param>
/// <param name="topDirectoryOnly">
/// Specifies whether to search the current directory, or the current directory and all
/// subdirectories
/// </param>
/// <returns>
/// An array of the full names (including paths) of the subdirectories that match
/// the specified criteria, or an empty array if no directories are found
/// </returns>
string[] GetDirectories(string path, string searchPattern = "", bool topDirectoryOnly = true);
/// <summary>
/// Returns the directory information for the specified path string
/// </summary>
/// <param name="path">The path of a file or directory</param>
/// <returns>
/// Directory information for path, or null if path denotes a root directory or is null. Returns
/// System.String.Empty if path does not contain directory information
/// </returns>
string GetDirectoryName(string path);
/// <summary>
/// Returns the directory name only for the specified path string
/// </summary>
/// <param name="path">The path of directory</param>
/// <returns>The directory name</returns>
string GetDirectoryNameOnly(string path);
/// <summary>
/// Returns the extension of the specified path string
/// </summary>
/// <param name="filePath">The path string from which to get the extension</param>
/// <returns>The extension of the specified path (including the period ".")</returns>
string GetFileExtension(string filePath);
/// <summary>
/// Returns the file name and extension of the specified path string
/// </summary>
/// <param name="path">The path string from which to obtain the file name and extension</param>
/// <returns>The characters after the last directory character in path</returns>
string GetFileName(string path);
/// <summary>
/// Returns the file name of the specified path string without the extension
/// </summary>
/// <param name="filePath">The path of the file</param>
/// <returns>The file name, minus the last period (.) and all characters following it</returns>
string GetFileNameWithoutExtension(string filePath);
/// <summary>
/// Returns the names of files (including their paths) that match the specified search
/// pattern in the specified directory, using a value to determine whether to search subdirectories.
/// </summary>
/// <param name="directoryPath">The path to the directory to search</param>
/// <param name="searchPattern">
/// The search string to match against the names of files in path. This parameter
/// can contain a combination of valid literal path and wildcard (* and ?) characters
/// , but doesn't support regular expressions.
/// </param>
/// <param name="topDirectoryOnly">
/// Specifies whether to search the current directory, or the current directory and all
/// subdirectories
/// </param>
/// <returns>
/// An array of the full names (including paths) for the files in the specified directory
/// that match the specified search pattern, or an empty array if no files are found.
/// </returns>
string[] GetFiles(string directoryPath, string searchPattern = "", bool topDirectoryOnly = true);
/// <summary>
/// Returns the date and time the specified file or directory was last accessed
/// </summary>
/// <param name="path">The file or directory for which to obtain access date and time information</param>
/// <returns>A System.DateTime structure set to the date and time that the specified file</returns>
DateTime GetLastAccessTime(string path);
/// <summary>
/// Returns the date and time the specified file or directory was last written to
/// </summary>
/// <param name="path">The file or directory for which to obtain write date and time information</param>
/// <returns>
/// A System.DateTime structure set to the date and time that the specified file or directory was last written to.
/// This value is expressed in local time
/// </returns>
DateTime GetLastWriteTime(string path);
/// <summary>
/// Returns the date and time, in coordinated universal time (UTC), that the specified file or directory was last
/// written to
/// </summary>
/// <param name="path">The file or directory for which to obtain write date and time information</param>
/// <returns>
/// A System.DateTime structure set to the date and time that the specified file or directory was last written to.
/// This value is expressed in UTC time
/// </returns>
DateTime GetLastWriteTimeUtc(string path);
/// <summary>
/// Retrieves the parent directory of the specified path
/// </summary>
/// <param name="directoryPath">The path for which to retrieve the parent directory</param>
/// <returns>The parent directory, or null if path is the root directory, including the root of a UNC server or share name</returns>
string GetParentDirectory(string directoryPath);
/// <summary>
/// Checks if the path is directory
/// </summary>
/// <param name="path">Path for check</param>
/// <returns>True, if the path is a directory, otherwise false</returns>
bool IsDirectory(string path);
/// <summary>
/// Maps a virtual path to a physical disk path.
/// </summary>
/// <param name="path">The path to map. E.g. "~/bin"</param>
/// <returns>The physical path. E.g. "c:\inetpub\wwwroot\bin"</returns>
string MapPath(string path);
/// <summary>
/// Reads the contents of the file into a byte array
/// </summary>
/// <param name="filePath">The file for reading</param>
/// <returns>A byte array containing the contents of the file</returns>
byte[] ReadAllBytes(string filePath);
/// <summary>
/// Opens a file, reads all lines of the file with the specified encoding, and then closes the file.
/// </summary>
/// <param name="path">The file to open for reading</param>
/// <param name="encoding">The encoding applied to the contents of the file</param>
/// <returns>A string containing all lines of the file</returns>
string ReadAllText(string path, Encoding encoding);
/// <summary>
/// Sets the date and time, in coordinated universal time (UTC), that the specified file was last written to
/// </summary>
/// <param name="path">The file for which to set the date and time information</param>
/// <param name="lastWriteTimeUtc">
/// A System.DateTime containing the value to set for the last write date and time of path.
/// This value is expressed in UTC time
/// </param>
void SetLastWriteTimeUtc(string path, DateTime lastWriteTimeUtc);
/// <summary>
/// Writes the specified byte array to the file
/// </summary>
/// <param name="filePath">The file to write to</param>
/// <param name="bytes">The bytes to write to the file</param>
void WriteAllBytes(string filePath, byte[] bytes);
/// <summary>
/// Creates a new file, writes the specified string to the file using the specified encoding,
/// and then closes the file. If the target file already exists, it is overwritten.
/// </summary>
/// <param name="path">The file to write to</param>
/// <param name="contents">The string to write to the file</param>
/// <param name="encoding">The encoding to apply to the string</param>
void WriteAllText(string path, string contents, Encoding encoding);
}step 2:
public class NopFileProvider : PhysicalFileProvider, INopFileProviderNopFileProvider<->INopFileProvider
PhysicalFileProvider<->Microsoft.Extensions.FileProviders.IFileProvider
INopFileProvider<-Microsoft.Extensions.FileProviders.IFileProvider