Evaluating numeric expressions

[PatrickS]

Is there an easy way in C# to take a string that contains an expression, say
for example something like '(10 / 2) + 1' and evaluate it without having to
parse the string myself and muck about with other stuff like operator
precedence?

 

[Frank Uray]

Maybe you can try with RegularExpressions

string local_pattern = @"[^0-9]";
System.Text.RegularExpressions.Regex local_RegEx = new
System.Text.RegularExpressions.Regex(local_pattern);
return local_RegEx.Replace(local_InputString, "");

 

[Leo Seccia]

isn't that going to return 1021? what kind of evaluation is that?

Maybe you can try with RegularExpressions

string local_pattern = @"[^0-9]";
System.Text.RegularExpressions.Regex local_RegEx = new
System.Text.RegularExpressions.Regex(local_pattern);
return local_RegEx.Replace(local_InputString, "");

Is there an easy way in C# to take a string that contains an expression, say
for example something like '(10 / 2) + 1' and evaluate it without having to
parse the string myself and muck about with other stuff like operator
precedence?

 

[Ben Voigt [C++ MVP]]

Is there an easy way in C# to take a string that contains an
expression, say for example something like '(10 / 2) + 1' and
evaluate it without having to parse the string myself and muck about
with other stuff like operator precedence?

You can invoke the C# compiler to create a class with a static method, then
call the method. Doing this without memory leaks is not easy and very bad
performance.

I would look into JScript.NET which has an eval function.

 

[Arne Vajhøj]

Is there an easy way in C# to take a string that contains an expression, say
for example something like '(10 / 2) + 1' and evaluate it without having to
parse the string myself and muck about with other stuff like operator
precedence?

JavaScript has a nice eval function that can be utilized from C#.

See http://www.vajhoej.dk/arne/eksperten/div_2007_08/evaljs.cs for
a code example.

Arne