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copied!<p>I have built something similar to what you are looking to construct. I built around using Expression trees from System.Linq.Expressions. So I would suggest that you build your where predicate using an expression tree where the predicate has the signature of <code>Expression<Func<T,bool>></code>. </p> <p>Some pseudo code below where T is a WCF RIA entity:</p> <pre><code>public static class QueryHelper { public static Expression<Func<T, bool>> ToPredicate<T> ( string propertyName, dynamic criteria ) { ParameterExpression pe = Expression.Parameter( typeof( T ), "t" ); Expression np = Expression.Property( pe, propertyName ); ConstantExpression value = Expression.Constant( criteria ); Expression e1 = Expression.Equal( np, value ); var filter = Expression.Lambda<Func<T, bool>>( e1, pe ); return filter; } } </code></pre> <p>Which could then be used like:</p> <pre><code>var selector = QueryHelper.ToPredicate<Category>("theColumn", "hello"); return this.ObjectContext.Categories.Where(selector); LoadOperation<Employee> loader = context.Load( context.GetEmployeesQuery() .Where( selector ) ); loader.Completed += (op) => { if ( !op.HasErrors) { } }; </code></pre> <p>Or</p> <pre><code>var selector = QueryHelper.ToPredicate<Category>("theColumn", true); return this.ObjectContext.Categories.Where(selector); </code></pre> <p>One thing to note is the line Expression e1 = Expression.<strong>Equal</strong>( np, value ); in the function. You could extend this function to do >, <, =>, etc but you would need to check that the property type you were using supported the operator.</p> <p>Hope this helps.</p>

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