How to implement the following function/method?

[Guest]

What's the best easy way to have a function/method:

1. Has a string paramter, the value of string is C#/VB.Net express.
2. The function evaluate the express and return the value.

 

[Joza]

What's the best easy way to have a function/method:

1. Has a string paramter, the value of string is C#/VB.Net express.
2. The function evaluate the express and return the value.

The question is what do you want to evaluate?


string YourFunction (string strParameter)
{
string result;

// Code for something to evaluate

return result;
}

 

[Guest]

the parameter will have some value like:

"100>10 && 100<1000 ? 1 : 0"
"'a' in ('a','b','c')"
etc.

 

[rossum]

What's the best easy way to have a function/method:

1. Has a string paramter, the value of string is C#/VB.Net express.
2. The function evaluate the express and return the value.

I don't know if this is the best/easiest way, but it is a way.

The parameter string has to be a complete compilable program, or at
least something that can be turned into a complete program easily.

1 If needed turn the parameter string into a string containing a
complete program.
2 Save the complete program string to a file.
3 Invoke the C# compiler to compile the program file into an exe file.
4 Invoke the newly created exe file.
5 Retrieve and return the result.

rossum

 

[Joza]

the parameter will have some value like:

"100>10 && 100<1000 ? 1 : 0"
"'a' in ('a','b','c')"
etc.

ok. but be more precisely. I'm little bit confused right now what do you really want?
Do you need algorithm for extracting some values from given parameter or something else?

 

[Jon Skeet [C# MVP]]

I don't know if this is the best/easiest way, but it is a way.

The parameter string has to be a complete compilable program, or at
least something that can be turned into a complete program easily.

1 If needed turn the parameter string into a string containing a
complete program.
2 Save the complete program string to a file.
3 Invoke the C# compiler to compile the program file into an exe file.
4 Invoke the newly created exe file.
5 Retrieve and return the result.

If you use CSharpCodeProvider, you don't need to write it to file or
convert it into an executable - just compile it from memory and into
memory. I'm doing that all the time at the moment, and it works well.

 

[Guest]

What's the best easy way to have a function/method:

1. Has a string paramter, the value of string is C#/VB.Net express.
2. The function evaluate the express and return the value.

If you can live with JavaScript syntax, then JScript has a nice
eval function for doing this.

And a JScript class with a wrapper method can be called
from C#.

Arne