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FieldInfo.IsFamilyOrAssembly Property

Definition

Gets a value indicating whether the potential visibility of this field is described by FamORAssem; that is, the field can be accessed by derived classes wherever they are, and by classes in the same assembly.

public:
 property bool IsFamilyOrAssembly { bool get(); };
public bool IsFamilyOrAssembly { get; }
member this.IsFamilyOrAssembly : bool
Public ReadOnly Property IsFamilyOrAssembly As Boolean

Property Value

true if access to this field is exactly described by FamORAssem; otherwise, false.

Implements

Examples

The following code example defines fields with varying levels of visibility, and displays the values of their IsAssembly, IsFamily, IsFamilyOrAssembly, and IsFamilyAndAssembly properties.

using namespace System;
using namespace System::Reflection;

public ref class Example
{
public:
    int f_public;
internal:
    int f_internal;
protected:
    int f_protected;
protected public:
    int f_protected_public;
protected private:
    int f_protected_private;
};

void main()
{
    Console::WriteLine("\n{0,-30}{1,-18}{2}", "", "IsAssembly", "IsFamilyOrAssembly"); 
    Console::WriteLine("{0,-21}{1,-18}{2,-18}{3}\n", 
        "", "IsPublic", "IsFamily", "IsFamilyAndAssembly");

    for each (FieldInfo^ f in Example::typeid->GetFields(
        BindingFlags::Instance | BindingFlags::NonPublic | BindingFlags::Public))
    {
        Console::WriteLine("{0,-21}{1,-9}{2,-9}{3,-9}{4,-9}{5,-9}", 
            f->Name,
            f->IsPublic,
            f->IsAssembly,
            f->IsFamily,
            f->IsFamilyOrAssembly,
            f->IsFamilyAndAssembly
        );
    }
}

/* This code example produces output similar to the following:

                              IsAssembly        IsFamilyOrAssembly
                     IsPublic          IsFamily          IsFamilyAndAssembly

f_public             True     False    False    False    False
f_internal           False    True     False    False    False
f_protected          False    False    True     False    False
f_protected_public   False    False    False    True     False
f_protected_private  False    False    False    False    True
 */
using System;
using System.Reflection;

public class Example
{
    public int f_public;
    internal int f_internal;
    protected int f_protected;
    protected internal int f_protected_public;
    private protected int f_private_protected;

    public static void Main()
    {
        Console.WriteLine("\n{0,-30}{1,-18}{2}", "", "IsAssembly", "IsFamilyOrAssembly");
        Console.WriteLine("{0,-21}{1,-18}{2,-18}{3}\n",
            "", "IsPublic", "IsFamily", "IsFamilyAndAssembly");

        foreach (FieldInfo f in typeof(Example).GetFields(
            BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public))
        {
            Console.WriteLine("{0,-21}{1,-9}{2,-9}{3,-9}{4,-9}{5,-9}",
                f.Name,
                f.IsPublic,
                f.IsAssembly,
                f.IsFamily,
                f.IsFamilyOrAssembly,
                f.IsFamilyAndAssembly
            );
        }
    }
}

/* This code example produces output similar to the following:

                              IsAssembly        IsFamilyOrAssembly
                     IsPublic          IsFamily          IsFamilyAndAssembly

f_public             True     False    False    False    False
f_internal           False    True     False    False    False
f_protected          False    False    True     False    False
f_protected_public   False    False    False    True     False
f_private_protected  False    False    False    False    True
 */
Imports System.Reflection

Public class Example

    Public f_Public As Integer
    Friend f_Friend As Integer 
    Protected f_Protected As Integer
    Protected Friend f_Protected_Friend As Integer
    Private Protected f_Private_Protected() As Integer

    Public Shared Sub Main()
    
        Console.WriteLine(vbCrLf & _
            "{0,-30}{1,-18}{2}", "", "IsAssembly", "IsFamilyOrAssembly") 
        Console.WriteLine("{0,-21}{1,-18}{2,-18}{3}" & vbCrLf, _
            "", "IsPublic", "IsFamily", "IsFamilyAndAssembly")
   
        For Each f As FieldInfo In GetType(Example).GetFields( _
            BindingFlags.Instance Or BindingFlags.NonPublic Or BindingFlags.Public)
        
            Console.WriteLine("{0,-21}{1,-9}{2,-9}{3,-9}{4,-9}{5,-9}", _
                f.Name, _
                f.IsPublic, _
                f.IsAssembly, _
                f.IsFamily, _
                f.IsFamilyOrAssembly, _
                f.IsFamilyAndAssembly _
            )
        Next
    End Sub
End Class

' This code example produces output similar to the following:
'
'                              IsAssembly        IsFamilyOrAssembly
'                     IsPublic          IsFamily          IsFamilyAndAssembly
'
'f_Public             True     False    False    False    False
'f_Friend             False    True     False    False    False
'f_Protected          False    False    True     False    False
'f_Protected_Friend   False    False    False    True     False
'f_Private_Protected  False    False    False    False    True

Remarks

If a field has FamORAssem level visibility, it can be called from any member in a derived class or any member in the same assembly, but not from any other type.

The actual visibility of a field is limited by the visibility of its type. The IsFamilyOrAssembly property might be true for a field, but if it is a field of a private nested type then the field is not visible outside the containing type.

The visibility of a field is exactly described by FieldAttributes.FamORAssem if the visibility modifier is protected internal in C# (Protected Friend in Visual Basic, protected public in C++).

Applies to

See also