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PONested groups using linq?
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  1. PONested groups using linq?
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    copied!<p>Lets say I have an object with the following properties.</p> <pre><code> public string VendorNumber { get; set; } public string PartNumber { get; set; } public string PartDivision { get; set; } </code></pre> <p>I have a list of about 300 of these objects. I am trying to group them first by VendorNumber, then by Division. I should be able to drill into them like so afterwards:</p> <ol> <li>Vendor A<br> Divsion 1<br> --Part 0001<br> --Part 0002<br> --Part 0003<br> Divsiion 2<br> --Part 0001</li> <li>Vendor B<br> Division 1<br> --Part 0023 ...etc...</li> </ol> <p>I can do the first grouping easily like so: </p> <pre><code>var vendorGroups = from v in vendors group v by v.VendorNumber into vg select new { VendorNumber = vg.Key, Parts = vg, Count = vg.Count() }; </code></pre> <p>I can't seem to get the nested grouping working though even after referring to some other posts here and on the MSDN. Thanks.</p> <hr> <p>Here is what I ended up with from the suggestions: </p> <p>I have made some progress using suggestions but I can't seem to access the second level when looping: </p> <pre><code>var vendorGroups = forecastHelpers .GroupBy(x =&gt; new { VendorNumber = x.VendorNumber, Division = x.PartDivision, Level = 1 }) .GroupBy(x =&gt; new { VendorNumber = x.Key.VendorNumber }).OrderBy(x =&gt; x.Key.VendorNumber); foreach (var vendorGroup in vendorGroups) { System.Diagnostics.Debug.WriteLine("VendorNumber: " + vendorGroup.Key.VendorNumber); foreach (var divisionGroup in vendorGroup) { System.Diagnostics.Debug.WriteLine(" Division: " + divisionGroup.Key.Division); foreach (var partNumber in divisionGroup) { System.Diagnostics.Debug.WriteLine(" PartNumber: " + partNumber.PartNumber); } } } </code></pre> <hr> <p>Update 2: This could also be written like so:</p> <pre><code>var vendorGroupings = from f in forecastHelpers group f by new { VendorNumber = f.VendorNumber, Division = f.PartDivision, Level = 2 } into vendorGroups from divisionGroups in (from division in vendorGroups orderby division.PartDivision group division by new { Division = division.PartDivision }) orderby vendorGroups.Key.VendorNumber group divisionGroups by new { VendorNumber = vendorGroups.Key.VendorNumber, Level = 1 }; foreach (var vendorGroup in vendorGroupings) { System.Diagnostics.Debug.WriteLine("VendorNumber: " + vendorGroup.Key.VendorNumber); foreach (var division in vendorGroup) { System.Diagnostics.Debug.WriteLine(" Division: " + division.Key.Division); foreach (var part in division) { System.Diagnostics.Debug.WriteLine(" PartNumber: " + part.PartNumber); } } </code></pre>
 

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