How do i get the decimal value of a unicode character in C#?

It's basically the same as Java. If you've got it as a char, you can just convert to int implicitly:

char c = '\u0b85';

// Implicit conversion: char is basically a 16-bit unsigned integer
int x = c;
Console.WriteLine(x); // Prints 2949

If you've got it as part of a string, just get that single character first:

string text = GetText();
int x = text[2]; // Or whatever...

Note that characters not in the basic multilingual plane will be represented as two UTF-16 code units. There is support in .NET for finding the full Unicode code point, but it's not simple.

((int)'அ').ToString()

If you have the character as a char, you can cast that to an int, which will represent the character's numeric value. You can then print that out in any way you like, just like with any other integer.

If you wanted hexadecimal output instead, you can use:

((int)'அ').ToString("X4")

X is for hexadecimal, 4 is for zero-padding to four characters.