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PONull Reference Exception while adding new Row to DataTable
 

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plurals
  1. PONull Reference Exception while adding new Row to DataTable
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    <p>I'm having this strange issue while adding a new row to a <code>DataTable</code>. It does not occur every time, but while running the application, I get null reference exception while there are no objects found null. </p> <p>Here is the code:</p> <p><em>Firstly Clear the Row and Columns of the DataTable:</em></p> <pre><code>dtLibraries.Rows.Clear(); dtLibraries.Columns.Clear(); dtLibraries.Columns.Add("Col1"); dtLibraries.Columns.Add("Col2"); dtLibraries.Columns.Add("Col3"); dtLibraries.Columns.Add("Col4"); dtLibraries.Columns.Add("Col5"); dtLibraries.Columns.Add("Col6"); dtLibraries.Columns.Add("Col7"); dtLibraries.Columns.Add("Col8"); dtLibraries.Columns.Add("Col9"); </code></pre> <p><em>Then reading another DataTable and Writing Data to this table:</em> </p> <pre><code>for (int s = 0; s &lt;= dttemp.Rows.Count - 1; s++) { dttemp1.Clear(); dttemp1 = business.GetOutputLibraries("SimObjectOutputRequestSet", dttemp.Rows[s].ItemArray[2].ToString(), dttemp.Rows[s].ItemArray[1].ToString(), dttemp.Rows[s].ItemArray[0].ToString()); for (int j = 0; j &lt;= dttemp1.Rows.Count - 1; j++) { DataRow dr = dtLibraries.NewRow(); dr["Col1"] = dttemp1.Rows[j].ItemArray[0].ToString(); dr["Col2"] = dttemp1.Rows[j].ItemArray[1].ToString(); dr["Col3"] = dttemp1.Rows[j].ItemArray[2].ToString(); dr["Col4"] = dttemp.Rows[s].ItemArray[0].ToString(); dr["Col5"] = dttemp.Rows[s].ItemArray[2].ToString(); dr["Col6"] = dttemp.Rows[s].ItemArray[1].ToString(); dr["Col7"] = cmbObject.Text.ToString(); dr["Col8"] = cmbLibraryType.Text; dr["Col9"] = cmbLibrarySubType.Text; dtLibraries.Rows.Add(dr); /// Exception occurs on this line } } </code></pre> <p>StackTrace:</p> <pre class="lang-none prettyprint-override"><code>at System.Data.NameNode.Eval(DataRow row, DataRowVersion version) at System.Data.BinaryNode.EvalBinaryOp(Int32 op, ExpressionNode left, ExpressionNode right, DataRow row, DataRowVersion version, Int32[] recordNos) at System.Data.BinaryNode.Eval(DataRow row, DataRowVersion version) at System.Data.DataExpression.Invoke(DataRow row, DataRowVersion version) at System.Data.Index.AcceptRecord(Int32 record, IFilter filter) at System.Data.Index.ApplyChangeAction(Int32 record, Int32 action, Int32 changeRecord) at System.Data.Index.RecordStateChanged(Int32 record, DataViewRowState oldState, DataViewRowState newState) at System.Data.DataTable.RecordStateChanged(Int32 record1, DataViewRowState oldState1, DataViewRowState newState1, Int32 record2, DataViewRowState oldState2, DataViewRowState newState2) at System.Data.DataTable.SetNewRecordWorker(DataRow row, Int32 proposedRecord, DataRowAction action, Boolean isInMerge, Boolean suppressEnsurePropertyChanged, Int32 position, Boolean fireEvent, Exception&amp; deferredException) at System.Data.DataTable.InsertRow(DataRow row, Int64 proposedID, Int32 pos, Boolean fireEvent) at System.Data.DataRowCollection.Add(DataRow row) </code></pre>
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    1. PO
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      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USNiranjan Kala
    1. USNiranjan Kala
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    1. PL
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      1. LTLinked
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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      1. PTAnswer
    2. PO
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      1. PTAnswer
    1. VO
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      1. PONull Reference Exception while adding new Row to DataTable
      1. This table or related slice is empty.
      1. VTApproveEditSuggestion
    1. COwhat is dttemp1?which line exactly rise the error execption?
      singulars
      1. PONull Reference Exception while adding new Row to DataTable
      1. USSelalu_Ingin_Belajar
    2. COyour StackTrace doesn't has details like which method call raised exception, in which method exception occurred etc..
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      1. PONull Reference Exception while adding new Row to DataTable
      1. USdotNETbeginner
    3. CO@Selalu_Ingin_Belajar: it's another `DataTable`. I am converting that dataTable values to string, so i do not think that will cause error.
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      1. PONull Reference Exception while adding new Row to DataTable
      1. USNiranjan Kala
 

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