Interpolated Verbatim Strings in C# 8.0

Prerequisite: String Interpolation and Verbatim String

Before C# 8.0 you are allowed to use string interpolation($) and verbatim identifier(@) together but in a specific sequence. It means when you use $ token and @ token together, it is necessary that $ token must appear before the @ token. If you use the @ token before $ token, then the compiler will give you an error, like as shown in the below example:

Example 1:

// C# program to illustrate the use
// of interpolated verbatim strings
using System;

class GFG {

    // Main Method
    static void Main()
    {
        int Base = 10;
        int Height = 30;
        int area = (Base * Height) / 2;

        // Here, $ token appears before @ token
        Console.WriteLine("Finding the area of a triangle:");
        Console.WriteLine($@"Height = ""{Height}"" and Base = ""{Base}""");
        Console.WriteLine($@"Area = ""{area}""");
    }
}

Output:

Finding the area of a triangle:
Height = "30" and Base = "10"
Area = "150"

Example 2:

// C# program to illustrate the use
// of interpolated verbatim strings
using System;

class GFG {

    // Main Method
    static void Main()
    {
        int Base = 10;
        int Height = 30;
        int area = (Base * Height) / 2;

        // Here, @ token appears before $ token
        // But the compiler will give an error
        Console.WriteLine("Finding the area of a triangle:");
        Console.WriteLine(@ $"Height = ""{Height}"" and Base = ""{Base}""");
        Console.WriteLine(@ $"Area = ""{area}""");
    }
}

Error:

error CS1646: Keyword, identifier, or string expected after verbatim specifier: @
error CS1646: Keyword, identifier, or string expected after verbatim specifier: @

When we use a @ token before $ token, then the compiler gives an error. This problem is solved in C# 8.0, now you are allowed to use a @ token before $ token or $ token before @ token

$@"..."
Or
@$"..."

and the compiler will not give an error. As shown in the below example:

Example:

// C# program to illustrate the use
// of interpolated verbatim strings
using System;

namespace Geeks {

class GFG {

    // Main Method
    static void Main(string[] args)
    {
        int Base = 40;
        int Height = 80;
        int area = (Base * Height) / 2;
        Console.WriteLine("Finding the area of a triangle:");

        // Here, $ token appears before @ token
        Console.WriteLine($@"Height = ""{Height}"" and Base = ""{Base}""");

        // Here, @ token appears before $ token
        Console.WriteLine(@$"Area = ""{area}""");
    }
}
}

Output:

Finding the area of a triangle:
Height = "80" and Base = "40"
Area = "1600"