How to Compare Datatable values with SharePoint List Items?

Question

I have one SharePoint List. From Excel I will store the values in Data-table and fetch the values to List.If new values are adding to list is no problem.

If item is already there i want to update the item to list.

In my Datatable here I was changed the CanNum -1 to CanNum -update. So I want to compare sharepoint list items and datatable. In datatble I want to store only modified values after I want to update in list.

Here is my code :

if (oItems != null)
                             {
                                 ///Item updating
                                 Hashtable htValues = new Hashtable();
                                 string ID = oItems.ID.ToString();
                                 foreach (SPListItem items in sqlfields)
                                 {
                                     string columns = items["Title"].ToString();
                                     string columns1 = items["Fields"].ToString();

                                         DataTable changedRecordsTable = dt.GetChanges(DataRowState.Modified);

                                         if (changedRecordsTable!=null)
                                         {
                                             if (changedRecordsTable.Columns.Contains(Sqlcolumns))
                                             {
                                               if (!htValues.Contains(columns1 ))
                 htValues.Add(columns1 , dr[columns]);
                                             }
                                         }

                                 }

                                 ///Using AddUpdateSqlItem method Update Product list witH SQL data's.
                                 oItems = UpdateItem(currWeb, olistname, ID, htValues);

I was tried this DataTable changedRecordsTable = dt.GetChanges(DataRowState.Modified); changedRecordsTable comes null.

In hashtable i want to add only modified values.

Based on that image i want to store only txtCan_ReqNum value to hastable.

How can i do this.Someone help for this. Thanks in Advance.

Answer 1

After adding or updating the value in datatable, you need to update it using below line.

dt.AcceptChanges();

I think you need to update the value in datatable & than after store it to the hashtable. so you will get the modified data.

below line will get the modified data from datatable

DataTable changedRecordsTable = dt.GetChanges(DataRowState.Modified);

After that you will get the result in changedRecordsTable

Please try this and let me know if it won't work.