Error with C# Partial classes

Question

I am using partial classes to split some functionality between 2 files, but I am getting an error. What am I doing wrong?

A1.cs:

private partial class A
{
    private string SomeProperty { get { return "SomeGeneratedString"; } }       
}

A2.cs:

private partial class A
{
    void SomeFunction()
    {
        //trying to access this.SomeProperty produces the following compiler error, at least with C# 2.0
        //error CS0117: 'A' does not contain a definition for 'SomeProperty'
    }
}

Answer 1

Are the two partial classes in the same namespace? That could be an explanation.

Answer 2

different namespace?

Answer 3

I think it's because you're declaring your class as "private". Try changing the modifier to "internal" so that the two "halves" of the class can "see" each other within the same assembly.

Answer 4

The error I get is:

Elements defined in a namespace cannot be explicitly declared as private, protected, or protected internal

I'm guessing it's a namespace issue as previously stated.

Answer 5

At first, I was unable to reproduce your error.

When these partial classes are defined alone, inside a namespace, the private keyword causes the build to fail with "Elements defined in a namespace cannot be explicitly declared as private, protected, or protected internal"...

If I keep them private and nest them within another class, everything works fine.

I can reproduce your error only when, in one file, I have part of the class nested inside another class, and in another file, I do NOT nest the class, and then remove the private keyword... like this:

Class1.cs:

namespace stackoverflow.answers
{
    public class Foo
    {
        private partial class Bar
        {
            private string SomeProperty { get { return "SomeGeneratedString"; } }
        }
    }
}

Class2.cs:

namespace stackoverflow.answers
{
    partial class Bar
    {
        void SomeFunction()
        {
            string bar = this.SomeProperty;
        }
    }    
}

I also get the error you described if the namespaces differ.

Please post the entire code for the solution, because the provided code is invalid C# syntax, and can't be looked into without more context.

Answer 6

I analyze your code. you declared partial class as nested class this is cause to show error. why bcz partial class will not declare as nested class the parial keyword is split into ultiple files so, every file nae is same when you declared in nested class it will not recognize.