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POIn LINQ how to use column value passed to IQueryable function with func<T,T2>
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Let's say I have this function to add a simple filter to my query: <pre><code> public static IQueryable<MyType> FilterSpecificParam(this IQueryable<MyType> query, string param) { var req = query.Where(c => (!(param == null || param.Trim() == "") && c.SpecificColumn.StartsWith(param)) || ((param == null || param.Trim() == ""))); return req; } </code></pre> I would use it like this: <pre><code>SomeQueryOnMyTable.FilterSpecificParam(MyFilter) </code></pre> Now, I don't want to repeat such a function for every filter I want to set! So, I figured out that I could write my query like this : <pre><code>SomeQueryOnMyTable.FilterGenericParam(MyFilter, c => c.TheColumnIWantToTest)) </code></pre> having this prototype for my function: <pre><code> public static IQueryable<MyType> Filter(this IQueryable<MyType> query, string param, Func<MyType, string> predicate) </code></pre> The problem: I don't manage to get a hand on the value of the column: <pre><code> public static IQueryable<MyType> Filter(this IQueryable<MyType> query, string param, Func<MyType, string> predicate) { var req = query.Where(c => (!(param == null || param.Trim() == "") && predicate.Invoke(What???).StartsWith(param)) || ((param == null || param.Trim() == ""))); return req; } </code></pre> Notice the predicate.Invoke in the code above: it asks for an argument of type MyType. I'd like it to take the argument of the preceding query (SomeQueryOnMyTable), but I don't have a clue of how to do this... Any idea? EDIT: Maybe there is a better way to do this generic filter function, I will eventually accept it as an answer
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<c#><linq><predicate><func>
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In LINQ how to use column value passed to IQueryable function with func<T,T2>
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1. COTake a look at this [How can I get objects and property values from expression trees?](http://blogs.msdn.com/b/csharpfaq/archive/2010/03/11/how-can-i-get-objects-and-property-values-from-expression-trees.aspx) Hope it helps.
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