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POFilter and keep first object of a List of objects with properties that match
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  1. POFilter and keep first object of a List of objects with properties that match
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    copied!<p>I apologize upfront, because I now realize that I have completely worded my example wrong. For those who have given responses, I truly appreciate it. Please let me re-attempt to explain with a more accurate details. Please edit your responses, and once again, I apologize for not being more exact in my previous posting.</p> <p>Using an entity framework model class called Staging (which is a representation of my Staging table), I have the following <code>List&lt;Staging&gt;</code>.</p> <pre><code>List&lt;Staging&gt; data = (from t in database.Stagings select t).ToList(); //check for an empty List...react accordingly... </code></pre> <p>Here is a quick look at what <code>Staging</code> looks like:</p> <pre><code>public partial class Staging { public int ID { get; set; } //PK public int RequestID { get; set; } //FK ... public string Project { get; set; } ... } </code></pre> <p>Let us suppose that the query returns 10 records into my <code>data</code> list. Let us also suppose that <code>data[3]</code>, <code>data[6]</code>, and <code>data[7]</code> each have the same value in <code>data.Project</code>, let's say <code>"Foo"</code>. The <code>data.Project</code> value is not known until runtime.</p> <p>Given this, how would I keep the first occurrence, <code>data[3]</code>, and remove <code>data[6]</code> and <code>data[7]</code> from my <code>List&lt;Staging&gt;</code>?</p> <p><strong>Edit:</strong> I have the following code that works, but is there another way?</p> <pre><code> HashSet&lt;string&gt; projectValuesFound = new HashSet&lt;string&gt;(); List&lt;Staging&gt; newData = new List&lt;Staging&gt;(); foreach (Staging entry in data) { if (!projectValuesFound.Contains(entry.Project)) { projectValuesFound.Add(entry.Project); newData.Add(entry); } } </code></pre>
 

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