C# Eval Expression Safe Mode Option

Problem

You want to allow your users to create and evaluate some generic expression. However, you need to limit access on what user can do!

Solution

Use the SafeMode property.

When enabled, the user can only use registered:

• Constructor
• Field
• Method
• Property

Example

var context = new EvalContext();
context.SafeMode = true;
context.UnregisterAll();
context.RegisterDefaultAliasSafe();

return context.Eval("1+2");