FileInfo::IsReadOnly Property

.NET Framework (current version)

Gets or sets a value that determines if the current file is read only.

Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)

Syntax

public:
property bool IsReadOnly {
	bool get();
	void set(bool value);
}

Property Value

Type: System::Boolean

true if the current file is read only; otherwise, false.

Exceptions

Exception	Condition
FileNotFoundException	The file described by the current FileInfo object could not be found.
IOException	An I/O error occurred while opening the file.
UnauthorizedAccessException	This operation is not supported on the current platform. -or- The caller does not have the required permission.
ArgumentException	The user does not have write permission, but attempted to set this property to false.

Remarks

Use the IsReadOnly property to quickly determine or change whether the current file is read only.

When first called, FileInfo calls Refresh and caches information about the file. On subsequent calls, you must call Refresh to get the latest copy of the information.

Examples

The following example uses the IsReadOnly property to mark a file as read only and then mark it as read-write.

C++

using namespace System;
using namespace System::IO;

namespace FileSystemExample
{
    // Sets the read-only value of a file.
    void SetFileReadAccess(String^ fileName, bool setReadOnly)
    {
        // Create a new FileInfo object.
        FileInfo^ fInfo = gcnew FileInfo(fileName);

        // Set the IsReadOnly property.
        fInfo->IsReadOnly = setReadOnly;
    }

    // Returns whether a file is read-only.
    bool IsFileReadOnly(String^ fileName)
    {
        // Create a new FileInfo object.
        FileInfo^ fInfo = gcnew FileInfo(fileName);

        // Return the IsReadOnly property value.
        return fInfo->IsReadOnly;
    }
}

int main()
{
    try
    {
		String^ fileName = "c:\\test.xml";

        if (File::Exists(fileName))
        {
            // Get the read-only value for a file.
            bool isReadOnly = FileSystemExample::IsFileReadOnly(fileName);

            // Display whether the file is read-only.
            Console::WriteLine("The file read-only value for {0} is:" +
                "{1}", fileName, isReadOnly);

            Console::WriteLine("Changing the read-only value for {0}" +
                " to true.", fileName);

            // Set the file to read-only.
            FileSystemExample::SetFileReadAccess(fileName, true);

            // Get the read-only value for a file.
            isReadOnly = FileSystemExample::IsFileReadOnly(fileName);

            // Display that the file is read-only.
            Console::WriteLine("The file read-only value for {0} is:" +
                "{1}", fileName, isReadOnly);
        }
        else
        {
            Console::WriteLine("The file {0} doesn't exist.", fileName);
        }
    }
    catch (IOException^ ex)
    {
        Console::WriteLine(ex->Message);
    }
};
//This code produces output similar to the following; 
//results may vary based on the computer/file structure/etc.:
//
//The file read-only value for c:\test.xml is:False
//Changing the read-only value for c:\test.xml to true.
//The file read-only value for c:\test.xml is:True