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copied!<p>What about this?</p> <pre><code>public class KeyGeneratorVisitor : ExpressionVisitor { protected override Expression VisitParameter(ParameterExpression node) { return Expression.Parameter(node.Type, node.Type.Name); } protected override Expression VisitMember(MemberExpression node) { if (CanBeEvaluated(node)) { return Expression.Constant(Evaluate(node)); } else { return base.VisitMember(node); } } private static bool CanBeEvaluated(MemberExpression exp) { while (exp.Expression.NodeType == ExpressionType.MemberAccess) { exp = (MemberExpression) exp.Expression; } return (exp.Expression.NodeType == ExpressionType.Constant); } private static object Evaluate(Expression exp) { if (exp.NodeType == ExpressionType.Constant) { return ((ConstantExpression) exp).Value; } else { MemberExpression mexp = (MemberExpression) exp; object value = Evaluate(mexp.Expression); FieldInfo field = mexp.Member as FieldInfo; if (field != null) { return field.GetValue(value); } else { PropertyInfo property = (PropertyInfo) mexp.Member; return property.GetValue(value, null); } } } } </code></pre> <p>This will replace the complex constant expressions to their original values as well as the parameter names to their type names. So just have to create a new <code>KeyGeneratorVisitor</code> instance and call its <code>Visit</code> or <code>VisitAndConvert</code> method with your expression.</p> <p>Please note that the <code>Expression.ToString</code> method will be also invoked on your complex types, so either override their <code>ToString</code> methods or write a custom logic for them in the <code>Evaluate</code> method.</p>

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