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copied!<p>In the general case this should work:</p> <pre><code>public static Expression<Func<T, bool>> Build(string propertyName, string method, params object[] args) { var propertyInfo = typeof(T).GetProperty(propertyName); var e = Expression.Parameter(typeof(T), "e"); var m = Expression.MakeMemberAccess(e, propertyInfo); var mi = m.Type.GetMethod(method, args.Select(a => a.GetType()).ToArray()); var c = args.Select(a => Expression.Constant(a, a.GetType())).ToArray(); Expression call = Expression.Call(m, mi, c); Expression<Func<T, bool>> lambda = Expression.Lambda<Func<T, bool>>(call, e); return lambda; } </code></pre> <p>The idea is that you accept any number of constant arguments, and use their types to select the appropriate overload when calling <code>GetMethod</code>. After that, you create the appropriate number of constant expressions from those arguments to pass to <code>Expression.Call</code>.</p> <p>So with the above code, you could do:</p> <pre><code>var l1 = LambdaExpressionHelper<MailingListMember>.Build( "EmailAddress", "StartsWith", "RoRy@"); var l2 = LambdaExpressionHelper<MailingListMember>.Build( "EmailAddress", "StartsWith", "RoRy@", StringComparison.OrdinalIgnoreCase); </code></pre> <p>If you also need to get the value <code>StringComparison.OrdinalIgnoreCase</code> from the string <code>"StringComparison.OrdinalIgnoreCase"</code>, I would factor this out into a separate method so that the interface of <code>Build</code> can remain generic. Exactly how to do it is covered in <a href="https://stackoverflow.com/questions/3565310/getting-enum-value-via-reflection">Getting Enum value via reflection</a> (and I guess in lots of similar questions as well).</p> <p><strong>Note</strong>: I don't have convenient access to a compiler right now, so please excuse any mistakes.</p>

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