C# - Marshalling a const char* return value from dll [duplicate]

Question

I have a function in a dll with the following identifier.

const char* function(void)

The DLL allocates the string on the heap and expects it only to be read. I have tried the following to import the function but am getting an access violation

[DllImport("great.dll", CharSet = CharSet.Ansi, 
                        CallingConvention = CallingConvention.Cdecl)
]
public static extern string function();

How do I handle this properly

Error message:

System.AccessViolationException: 'Attempted to read or write protected memory. This is often an indication that other memory is corrupt.'

Answer 1

Regarding the text in the question ""With other functions with the same parameter type, I have been able to use [MarshalAs(UnmanagedType.LPStr)] to handle it, but this will not work for return values."

quoting this from https://learn.microsoft.com/en-us/dotnet/api/system.runtime.interopservices.marshalasattribute?view=netframework-4.7

//Applied to a return value.
[return: MarshalAs(UnmanagedType.LPWStr)]
    public String GetMessage()
    {
        return "Hello World";
    }

update: keeping this in case it is helpful for others searching about "MarshalAs" and return values, since the author of the question has already solved their issue as they comment above