C# DataRow not Being Added to DataTable

Question

I created a DataTable and when I try to add a row to it, it does not take. I know that there is information in the DataRow, but after the foreach loop is finished, and I look at the DataTable's count, it shows 0. This is the code I'm using:

DataSet CustomColumnsDS = new DataSet();
DataTable dt = new DataTable();
string strXML = GetCatalog(WebUserID, Password); //Web Service Call
XmlDocument doc = new XmlDocument();doc.LoadXml(strXML);
XmlNodeList xnList = doc.SelectNodes("xml/Catalog/item/Package");

if (xnList.Count > 0)//Count = 90
{
dt.Columns.Add("testId", typeof(string));
dt.Columns.Add("testName", typeof(string));

foreach (XmlNode xn in xnList) 
{
    if (!string.IsNullOrEmpty(xn["Id"].InnerText))
    {
        DataRow dr = dt.NewRow();
        dr["testId"] = xn["Id"].InnerText;
        dr["testName"] = xn["Name"].InnerText;
        try
        {
            //At this point the DataRow is filled in with values, but it does not seem to actually add in.
            dt.Rows.Add(dr); //No Exception is caught
        }
        catch (Exception ex)
        {
            string test = "";
        }
    }
}
CustomColumnsDS.Tables.Add(dt);//Count = 0;
}

Any help is appreciated. Thanks!

Answer 1

I ran your code with the following sample xml (in-place of the web service call):

string strXML =
@"
    <xml>
        <Catalog>
            <item>
                <Package>
                    <Id>1</Id>
                    <Name>a</Name>
                </Package>
                <Package>
                    <Id>2</Id>
                    <Name>b</Name>
                </Package>
            </item>
            <item>
                <Package>
                    <Id>3</Id>
                    <Name>c</Name>
                </Package>
                <Package>
                    <Id>4</Id>
                    <Name>d</Name>
                </Package>        
            </item>
        </Catalog>
    </xml>                
    ";

I appended the following code to the end for debugging purposes:

Console.WriteLine(CustomColumnsDS.Tables[0].Rows.Count);

And the output was 4 which is correct. Also viewing the DataTable rows in the debugger revealed that the data is there.

Answer 2

You should try without assign type of column because we do not know the type of xml element, just try: dt.Columns.Add("testId"); dt.Columns.Add("testName"); Until try cacth... Are you sure you get correctly data for every datarow? (run debug until this line to see the value: dr["testName"] = xn["Name"].InnerText;