InfoPath 2007/2010/2013: Populate a Repeating Table from a Secondary Data Source

Psst! I have a new nested solution posted here.

Background
In attempting to create a solution within form code to satisfy the scenerio/requirements below, I found several different posts/links that described certain functions. Each link only provided a piece of the puzzle. This post puts all the pieces together.


Scenario/Requirements
Clicking a button or changing a selection in an InfoPath form needs to query a web service (or any secondary data source) based on that selection and populate a repeating table with the data. If the selection changes, the repeating table entries need to be cleared and re-populated with the new set of data.


Assumptions
The querying of the secondary data source (such as a web service) based on selections is already in place (this can be easily done with rules). We just need the proper form code within the control change-event to handle the repeating table population.



Solution Piece-by-Piece

Namespace Variable
Within the changed event form code (using Visual Studio for Office Applications) the first thing we need is the standard namespace variable so we can use that throughout:

string myNamespace = NamespaceManager.LookupNamespace("my");

Access Web Service-Based Secondary Data Source
There is a MainDataSource object at the form level but how can you access secondary data sources? If the datasource is named "GetData" here is the code to access and setup the XPath objects for looping:

DataSource ds = DataSources["GetData"];
XPathNavigator domNav = ds.CreateNavigator();
XPathNodeIterator rows = domNav.Select("/dfs:myFields/dfs:dataFields/tns:GetDataResponse/tns:GetData/NewDataSet/DynamicData", NamespaceManager);

Looping Through the Secondary Data Source
You can loop through the XPathNodeIterator collection using a while-loop. The source fields data can be retrieved by using the Current pointer within the XPathNodeIterator:

while (rows.MoveNext())
{string accountID = rows.Current.SelectSingleNode("AccountID",NamespaceManager).Value.ToString();
string accountNumber = rows.Current.SelectSingleNode("AccountNumber",NamespaceManager).Value.ToString();
string amount = rows.Current.SelectSingleNode("Amount",
NamespaceManager).Value.ToString }

Populating the Repeating Table
The repeating table is actually part of the main data source so we can access that and use the XMLWriter to write the field values from the web service to the table. The code below will live within the loop from above:

using (XmlWriter writer = MainDataSource.CreateNavigator().SelectSingleNode("/my:MainDataSource/my:group1", NamespaceManager).AppendChild())
{


writer.WriteStartElement("group2", myNamespace);
writer.WriteElementString("Amount",myNamespace ,amount);
writer.WriteElementString("AccountID", myNamespace, accountID);
writer.WriteElementString("AccountNumber", myNamespace,
accountNumber);
writer.WriteEndElement();
writer.Close();
}

The above assumes the repeating table created a Group1\Group2 data source entry. You must look at the main datasource to determine the group names.

ALSO! VERY IMPORTANT! The order in which you write the values to the table should be the order that they appear in the main data source. So if you expand the group1 and group2 and see field1, field2, field3, that is the order you must have in the code above. Otherwise you will receive a non-datatype schema validation error.

Clearing Previous Entries
Before anything happens, we need to check if there are already rows in the repeating table and remove them. This must be done by removing the rows in a descending fashion because the count actually represents the highest index.

First we check to see if there are any rows in the repeating table and if so we loop through and delete them. Notice how the actual row is accessed using the SelectSingleNode (SelectSingleNode("/my:MainDataSource/my:group1/my:group2[row#]):

XPathNavigator rTable = MainDataSource.CreateNavigator();
XPathNodeIterator tableRows = rTable.Select("/my:MainDataSource/my:group1/my:group2", NamespaceManager);
if (tableRows.Count > 0)
{


for (int i = tableRows.Count;i > 0; i--)
{
XPathNavigator reTable =
MainDataSource.CreateNavigator();
XPathNavigator reTableRows =
reTable.SelectSingleNode("/my:MainDataSource/my:group1/my:group2[" + i + "]", NamespaceManager);
reTableRows.DeleteSelf(); } }




Solution - Complete Code
//Get namespace
string myNamespace = NamespaceManager.LookupNamespace("my");
//Clear any previous entries
XPathNavigator rTable = MainDataSource.CreateNavigator(); XPathNodeIterator tableRows = rTable.Select("/my:MainDataSource/my:group1/my:group2", NamespaceManager);

if (tableRows.Count > 0)
{for (int i = tableRows.Count;i > 0; i--)
{
XPathNavigator reTable =
MainDataSource.CreateNavigator();
XPathNavigator reTableRows =
reTable.SelectSingleNode("/my:MainDataSource/my:group1/my:group2[" + i + "]",
NamespaceManager);
reTableRows.DeleteSelf();
}
}
//Connect to secondary data source
DataSource ds = DataSources["GetData"];
XPathNavigator domNav = ds.CreateNavigator(); XPathNodeIterator rows = domNav.Select("/dfs:myFields/dfs:dataFields/tns:GetDataResponse/tns:GetData/NewDataSet/DynamicData", NamespaceManager);

//Loop through secondary data source and populate the repeating table

while (rows.MoveNext())
{

string accountID =
rows.Current.SelectSingleNode("AccountID", NamespaceManager).Value.ToString();
string accountNumber =
rows.Current.SelectSingleNode("AccountNumber",NamespaceManager).Value.ToString();
string amount =
rows.Current.SelectSingleNode("Amount", NamespaceManager).Value.ToString();
using (XmlWriter writer =
MainDataSource.CreateNavigator().SelectSingleNode("/my:MainDataSource/my:group1",
NamespaceManager).AppendChild())

{
writer.WriteStartElement("group2", myNamespace);
writer.WriteElementString("Amount",myNamespace ,amount);
writer.WriteElementString("AccountID",
myNamespace, accountID);
writer.WriteElementString("AccountNumber", myNamespace,
accountNumber);
writer.WriteEndElement();
writer.Close(); }
}

WHAT ABOUT A NESTED REPEATING TABLE? THE ANSWER IS HERE!

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