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POIEnumerable has values but still gives System.NullReferenceException
 

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  1. POIEnumerable has values but still gives System.NullReferenceException
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    <p>I am populating an <code>IEnumerable</code> using a LINQ query. The <code>IEnumerable</code> is then passed into another class and appended as a parameter (to a Telerik report). On this line, I'm getting a <code>System.NullReferenceException</code>. Through debugging I've confirmed that this <code>IEnumerable</code> has a list of values so I'm not sure why this is happening.</p> <p>Here are some relevant snippets of my code:</p> <p><strong>Class1.cs</strong> </p> <pre><code>//Note that divisionList is an List of PKs and divisionTotalsList is a list of DivisionTotalsModel foreach (int division in divisionList) { //LINQ Query IEnumerable&lt;DivisionTotalsModel&gt; divSubset = from divno in divisionTotalsList where divno.DivisionNo == division select divno; //Create Report if(divSubset.Any()) Class2.DoStuff(divSubset); } </code></pre> <p><strong>Class2.cs</strong></p> <pre><code>public void DoStuff(IEnumerable&lt;DivisionTotalsModel&gt; divisionList){ using (var divisionTotalsReport = new DivisionReport()) { //There are other parameters here that are working successfully //This is the line that is failing divisionTotalsReport.ReportParameters["list"].Value = divisionList; } } </code></pre> <p>Why is the error occurring here?</p> <p>The <code>ReportParameters</code> are working with other parameters (<code>DateTime</code> and <code>int</code>), I just didn't include them in the code snippet.</p> <p>I've tried <code>ToList()</code> and successfully received a <code>List&lt;T&gt;</code>, but Telerik requires an <code>IEnumerable&lt;T&gt;</code>.</p> <p><strong>The issue has to lie with the new parameter</strong> because I've been able to successfully create the report previously using my other parameters (<code>DateTime</code> and <code>int</code>). The issue has only started when I've tried to add this new <code>IEnumerable</code> parameter.</p> <p>I've gone through the debugger and looked at the IEnumerable, it says the base is null but when I go to non public members -> source I can see the items.</p> <p><strong>Solution</strong></p> <p>I've figured out the problem, I was attempting to feed the data source as a parameter. I've set it as the data source instead and it works perfectly. </p>
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      1. POIEnumerable has values but still gives System.NullReferenceException
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    1. COPerhaps you could add the piece of code that initializes `ReportParameters` ?
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      1. POIEnumerable has values but still gives System.NullReferenceException
      1. USAndomar
    2. CODebug the code and see what is actually `null` on that line of code. It's probably not `divisionList`. Odds are that either `ReportParameters` is `null` or (probably more likely) whatever it's indexer returns is `null`.
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      1. USServy
    3. COHave you tried use `.ToArray` in linq?
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      1. USFendy
 

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