Class FileSupport

Represents the methods to support some operations over files.

Inheritance

System.Object

FileSupport

Namespace: Lucene.Net.Support.IO

Assembly: Lucene.Net.dll

Syntax

public static class FileSupport : object

Methods

CreateTempFile(String, String)

Creates a new empty file in a random subdirectory of , using the given prefix and suffix strings to generate its name.

Declaration

public static FileInfo CreateTempFile(string prefix, string suffix)

Parameters

Type	Name	Description
System.String	prefix	The prefix string to be used in generating the file's name; must be at least three characters long
System.String	suffix	The suffix string to be used in generating the file's name; may be null, in which case a random suffix will be generated

Returns

Type	Description
FileInfo	A instance representing the temp file that was created.

Remarks

If this method returns successfully then it is guaranteed that:

1. The file denoted by the returned abstract pathname did not exist before this method was invoked, and
2. Neither this method nor any of its variants will return the same abstract pathname again in the current invocation of the virtual machine.

This method provides only part of a temporary-file facility. However, the file will not be deleted automatically, it must be deleted by the caller.

The prefix argument must be at least three characters long. It is recommended that the prefix be a short, meaningful string such as "hjb" or "mail".

The suffix argument may be null, in which case a random suffix will be used.

Both prefix and suffix must be provided with valid characters for the underlying system, as specified by .

If the directory argument is null then the system-dependent default temporary-file directory will be used, with a random subdirectory name. The default temporary-file directory is specified by the method. On UNIX systems the default value of this property is typically "/tmp" or "/var/tmp"; on Microsoft Windows systems it is typically "C:\Users\[UserName]\AppData\Local\Temp".

CreateTempFile(String, String, DirectoryInfo)

Creates a new empty file in the specified directory, using the given prefix and suffix strings to generate its name.

Declaration

public static FileInfo CreateTempFile(string prefix, string suffix, DirectoryInfo directory)

Parameters

Type	Name	Description
System.String	prefix	The prefix string to be used in generating the file's name; must be at least three characters long
System.String	suffix	The suffix string to be used in generating the file's name; may be null, in which case a random suffix will be generated
DirectoryInfo	directory	The directory in which the file is to be created, or null if the default temporary-file directory is to be used

Returns

Type	Description
FileInfo	A instance representing the temp file that was created.

Remarks

If this method returns successfully then it is guaranteed that:

1. The file denoted by the returned abstract pathname did not exist before this method was invoked, and
2. Neither this method nor any of its variants will return the same abstract pathname again in the current invocation of the virtual machine.

This method provides only part of a temporary-file facility. However, the file will not be deleted automatically, it must be deleted by the caller.

The prefix argument must be at least three characters long. It is recommended that the prefix be a short, meaningful string such as "hjb" or "mail".

The suffix argument may be null, in which case a random suffix will be used.

Both prefix and suffix must be provided with valid characters for the underlying system, as specified by .

If the directory argument is null then the system-dependent default temporary-file directory will be used, with a random subdirectory name. The default temporary-file directory is specified by the method. On UNIX systems the default value of this property is typically "/tmp" or "/var/tmp"; on Microsoft Windows systems it is typically "C:\Users\[UserName]\AppData\Local\Temp".

GetCanonicalPath(FileSystemInfo)

Returns the absolute path of this with all references resolved and any drive letters normalized to upper case on Windows. An absolute path is one that begins at the root of the file system. The canonical path is one in which all references have been resolved. For the cases of '..' and '.', where the file system supports parent and working directory respectively, these are removed and replaced with a direct directory reference.

Declaration

public static string GetCanonicalPath(this FileSystemInfo path)

Parameters

Type	Name	Description
FileSystemInfo	path	This instance.

Returns

Type	Description
System.String	The canonical path of this file.

IsFileAlreadyExistsException(Exception, String)

Tests whether the passed in is an corresponding to the underlying operating system's "File Already Exists" violation. This works by forcing the exception to occur during initialization and caching the value for the current OS.

Declaration

public static bool IsFileAlreadyExistsException(Exception ex, string filePath)

Parameters

Type	Name	Description
Exception	ex	An exception, for comparison.
System.String	filePath	The path of the file to check. This is used as a fallback in case the current OS doesn't have an HResult (an edge case).

Returns

Type	Description
System.Boolean	true if the exception passed is an with an corresponding to the operating system's "File Already Exists" violation, which occurs when an attempt is made to create a file that already exists.