Path.Combine Method (System.IO) (original) (raw)
Source:
Source:
Source:
Source:
Combines two strings into a path.
public:
static System::String ^ Combine(System::String ^ path1, System::String ^ path2);public static string Combine(string path1, string path2);static member Combine : string * string -> stringPublic Shared Function Combine (path1 As String, path2 As String) As StringParameters
path1
The first path to combine.
path2
The second path to combine.
Returns
The combined paths. If one of the specified paths is a zero-length string, this method returns the other path. If path2 contains an absolute path, this method returns path2.
Exceptions
.NET Framework and .NET Core versions older than 2.1: path1 or path2 contains one or more of the invalid characters defined in GetInvalidPathChars().
Examples
The following example demonstrates using the Combine method on Windows.
using System;
using System.IO;
public class ChangeExtensionTest
{
public static void Main()
{
string path1 = "c:\\temp";
string path2 = "subdir\\file.txt";
string path3 = "c:\\temp.txt";
string path4 = "c:^*&)(_=@#'\\^.*(.txt";
string path5 = "";
CombinePaths(path1, path2);
CombinePaths(path1, path3);
CombinePaths(path3, path2);
CombinePaths(path4, path2);
CombinePaths(path5, path2);
}
private static void CombinePaths(string p1, string p2)
{
string combination = Path.Combine(p1, p2);
Console.WriteLine("When you combine '{0}' and '{1}', the result is: {2}'{3}'",
p1, p2, Environment.NewLine, combination);
Console.WriteLine();
}
}
// This code produces output similar to the following:
//
// When you combine 'c:\temp' and 'subdir\file.txt', the result is:
// 'c:\temp\subdir\file.txt'
//
// When you combine 'c:\temp' and 'c:\temp.txt', the result is:
// 'c:\temp.txt'
//
// When you combine 'c:\temp.txt' and 'subdir\file.txt', the result is:
// 'c:\temp.txt\subdir\file.txt'
//
// When you combine 'c:^*&)(_=@#'\^.*(.txt' and 'subdir\file.txt', the result is:
// 'c:^*&)(_=@#'\^.*(.txt\subdir\file.txt'
//
// When you combine '' and 'subdir\file.txt', the result is:
// 'subdir\file.txt'
Imports System.IO
Public Class ChangeExtensionTest
Public Shared Sub Main()
Dim path1 As String = "c:\temp"
Dim path2 As String = "subdir\file.txt"
Dim path3 As String = "c:\temp.txt"
Dim path4 As String = "c:^*&)(_=@#'\\^.*(.txt"
Dim path5 As String = ""
Dim path6 As String = Nothing
CombinePaths(path1, path2)
CombinePaths(path1, path3)
CombinePaths(path3, path2)
CombinePaths(path4, path2)
CombinePaths(path5, path2)
CombinePaths(path6, path2)
End Sub
Private Shared Sub CombinePaths(p1 As String, p2 As String)
Try
Dim combination As String = Path.Combine(p1, p2)
Console.WriteLine("When you combine '{0}' and '{1}', the result is: {2}'{3}'", p1, p2, Environment.NewLine, combination)
Catch e As Exception
If p1 = Nothing Then
p1 = "Nothing"
End If
If p2 = Nothing Then
p2 = "Nothing"
End If
Console.WriteLine("You cannot combine '{0}' and '{1}' because: {2}{3}", p1, p2, Environment.NewLine, e.Message)
End Try
Console.WriteLine()
End Sub
End Class
' This code produces output similar to the following:
'
' When you combine 'c:\temp' and 'subdir\file.txt', the result is:
' 'c:\temp\subdir\file.txt'
'
' When you combine 'c:\temp' and 'c:\temp.txt', the result is:
' 'c:\temp.txt'
'
' When you combine 'c:\temp.txt' and 'subdir\file.txt', the result is:
' 'c:\temp.txt\subdir\file.txt'
'
' When you combine 'c:^*&)(_=@#'\^.*(.txt' and 'subdir\file.txt', the result is:
' 'c:^*&)(_=@#'\^.*(.txt\subdir\file.txt'
'
' When you combine '' and 'subdir\file.txt', the result is:
' 'subdir\file.txt'
'
' You cannot combine '' and 'subdir\file.txt' because:
' Value cannot be null.
' Parameter name: path1
Remarks
If path1 is not a drive reference (that is, "C:" or "D:") and does not end with a valid separator character as defined in DirectorySeparatorChar, AltDirectorySeparatorChar, or VolumeSeparatorChar, DirectorySeparatorChar is appended to path1 before concatenation. Note that if path1 ends in a path separator character that is not appropriate for the target platform, the Combine method preserves the original path separator character and appends a supported one. The following example compares the result on Windows and Unix-based systems when the backslash is used as a path separator character.
var result = Path.Combine(@"C:\Pictures\", "Saved Pictures");
Console.WriteLine(result);
// The example displays the following output if run on a Windows system:
// C:\Pictures\Saved Pictures
//
// The example displays the following output if run on a Unix-based system:
// C:\Pictures\/Saved Pictures
Dim result = Path.Combine("C:\Pictures\", "Saved Pictures")
Console.WriteLine(result)
' The example displays the following output if run on a Windows system:
' C:\Pictures\Saved Pictures
'
' The example displays the following output if run on a Unix-based system:
' C:\Pictures\/Saved Pictures
If path2 does not include a root (for example, if path2 does not start with a separator character or a drive specification), the result is a concatenation of the two paths, with an intervening separator character. If path2 includes a root, path2 is returned.
The parameters are not parsed if they have white space. Therefore, if path2 includes white space (for example, " \file.txt "), the Combine method appends path2 to path1 instead of returning only path2.
.NET Framework and .NET Core versions older than 2.1: Not all invalid characters for directory and file names are interpreted as unacceptable by the Combine method, because you can use these characters for search wildcard characters. For example, while Path.Combine("c:\\", "*.txt") might be invalid if you were to create a file from it, it is valid as a search string. It is therefore successfully interpreted by the Combine method.
For a list of common I/O tasks, see Common I/O Tasks.
See also
- File path formats on Windows systems
- File and Stream I/O
- How to: Read Text from a File
- How to: Write Text to a File