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POHow to choose programaticaly the column to be queried by Linq using PropertyInfo?
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copied!<p>I would like to control how Linq queries my database programmatically. For instance, I'd like to query the column <strong>X</strong>, column <strong>Y</strong>, or column <strong>Z</strong>, depending on some conditions.</p> <p>First of all, I've created an array of all the properties inside my class called <code>myPropertyInfo</code>.</p> <pre><code>Type MyType = (typeOf(MyClass)); PropertyInfo[] myPropertyInfo = myType.GetProperties( BindingFlags.Public|BindingFlags.Instance); </code></pre> <p>The <code>myPropertyInfo</code> array allows me to access each property details (Name, propertyType, etc) through the index <code>[i]</code>.</p> <p>Now, how can I use the above information to control how Linq queries my DB?</p> <p>Here's a sample of a query I'd like to exploit.</p> <pre><code>var myVar = from tp in db.MyClass select tp.{expression}; </code></pre> <p><strong>Expression</strong> using <code>myPropertyInfo[i]</code> to choose which property (column) to query. </p> <p>I'm not sure if that's the way of doing it, but if there's another way to do so, I'll be glad to learn.</p> <p><strong>EDIT</strong>:</p> <p>I believe the right expression the one used by @Gabe. In fact, I'd like to make queries on the fly. Here's the reason: I've (i) a table <code>Organizations</code> (Ministries, Embassies, International Organizations, such as UN, UNPD, UNICEF, World Bank, etc, and services depending on them). I've (ii) an other table <code>Hierarchy</code> which represents the way those organizations are linked, starting by which category each one belongs to (Government, Foreign Missions, private sector, NGO, etc.) </p> <p>Each column representing a level in the hierarchy, some rows will be longer while other will be shorter. Many rows' columns will share the same value (for instance 2 ministries belonging to the government, will have "Government" as value for the column 'Level 1').</p> <p>That's why, for each row (organization), I need to go level by level (i.e. column by column).</p> <p>Hope I've been enough explicit this time</p> <p>Thanks for helping.</p>

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