Case Sensitivity

Functions and Parameters

By default, the evaluation process is case-sensitive. This means every parameter and function evaluation will match with case sensitivity. This behavior can be overriden for both using a IDictionary implementation with a custom StringComparer.

Case-insensitive function

var expression = new Expression("secretOperation()")
{
    Functions = new Dictionary<string, ExpressionFunction>(StringComparer.InvariantCultureIgnoreCase)
    {
        { "SecretOperation", (arguments) => 42 }
    }
};

Case-insensitive parameter

var expression = new Expression("name == 'Beatriz'")
{
    Parameters = new Dictionary<string, object>(StringComparer.InvariantCultureIgnoreCase)
    {
        { "Name", "Beatriz" }
    }
};

Case-insensitive built-in function

var expression = new Expression("aBs(-1)", ExpressionOptions.IgnoreCaseAtBuiltInFunctions);

String Comparison

You can also change the comparison of string values using CaseInsensitiveStringComparer.

 var expression = new Expression("{PageState} == 'list'");
 expression.Parameters["PageState"] = "List";
 Debug.Assert(false, expression.Evaluate());
 
 expression = new Expression("{PageState} == 'list'", ExpressionOptions.CaseInsensitiveStringComparer);
 expression.Parameters["PageState"] = "List";
 Debug.Assert(true, expression.Evaluate());