solve a string having bodmas equation

You are first going have to express your equations in a C# compatible format.

C# does not do implicit multiplication if two different expressions in parentheses are adjacent:

(7+((8%2)(7%3))) will not compile in C#: (7+((8%2)*(7%3))) will.

Transforming a string that does express implicit multiplication is, however, easy:

string equationString = "(7+((8%2)(7%3)))";
string explicitMultiply = equationString.Replace(")(", ")*(");

But, if you had an expression of the form "5(10)," and expected that to multiply 5 x 10: that would require another type of fix.