C# ASP.NET App: update listbox after write delete using dataset

[rrflore2]

Ok. I'm writing and deleting to an xml file using a dataset. I have a function in my codebehind page that binds a listbox to the dataset that performs the writes/deletes. Everything seems to be working fine except, I cannot get the listbox to update after the xml file is written to.

I've tried to rebind the listbox and a bunch of other things; nothing seems to work. I'm sure this is simple fix but, I cannot seem to figure it out.

I have provided some code below.

Thanks in advance!!!

using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.IO;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml;
 
public partial class _Default : System.Web.UI.Page
{
 
    DataSet ds = new DataSet();
    XmlDataDocument xmlDataDoc = new XmlDataDocument();
 
    protected void Page_Load(object sender, EventArgs e)
    {
         if (!Page.IsPostBack)
        {
 
            //Bind lstCategory to dsXml
            LoadCategories();
 
        }
 
     }
 
 
     protected void LoadCategories()
    {
 
        ds = GetCategoryDs();
 
        DataView dv = ds.Tables["Category"].DefaultView;
        dv.Sort = "CategoryText ASC";
 
        lstCategory.DataSource = ds;
        lstCategory.DataMember = "Category";
        lstCategory.DataTextField = "CategoryText";
        lstCategory.DataValueField = "CategoryValue";
        lstCategory.DataBind();
 
    }
 
    protected DataSet GetCategoryDs()
    {
 
        DataSet dsCategory = new DataSet();
        string filepath = Server.MapPath("xml") + "\\Categories.xml"; 
 
        dsCategory = xmlDataDoc.DataSet;
        dsCategory.ReadXml(filepath);
        dsCategory.ReadXmlSchema(filepath);
 
        return dsCategory;
 
    }
 
        protected void btnAddCategory_Click(object sender, EventArgs e)
    {
        if (txtCategroy.Text != "")
        {
 
            ds = GetCategoryDs();
            string filepath = Server.MapPath("xml") + "\\Categories.xml";
 
            DataRow dr = ds.Tables["Category"].NewRow();
            dr["CategoryText"] = txtCategroy.Text;
            dr["CategoryValue"] = txtCategroy.Text;
 
            ds.Tables["Category"].Rows.Add(dr);
 
            ds.WriteXml(filepath, XmlWriteMode.WriteSchema);
 
            ////Clear text box and change from xmldatasource to dataset and rebind listbox
            txtCategroy.Text = "";
            //LoadCategories();
            lstCategory.DataBind();
 
        }
 
    }
    protected void btnRemoveCategory_Click(object sender, EventArgs e)
    {
 
        if (lstCategory.SelectedItem != null)
        {
 
            ds = GetCategoryDs();
            string filepath = Server.MapPath("xml") + "\\Categories.xml";
 
            DataView dv = ds.Tables["Category"].DefaultView;
            dv.Sort = "CategoryText";
 
            int rowindex = dv.Find(lstCategory.SelectedItem.ToString());
 
            if (rowindex == -1)
                Response.Redirect("Error.aspx");
 
            else
            {
 
                dv.RowFilter = " CategoryText = '" + lstCategory.SelectedItem.ToString() + "'";
                dv.Delete(0);
                ds.WriteXml(filepath, XmlWriteMode.WriteSchema);
 
            }
 
            //LoadCategories();
            lstCategory.DataBind();
 
        }
 
    }
}

XML file snippet:

<?xml version="1.0" standalone="yes"?>
<Categories>
<xs:schema id="Categories" xmlns="" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
<xs:element name="Categories" msdata:IsDataSet="true" msdata:UseCurrentLocale="true" msdata:EnforceConstraints="False">
<xs:complexType>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element name="Category">
<xs:complexType>
<xs:sequence>
<xs:element name="CategoryValue" type="xs:string" minOccurs="0" />
<xs:element name="CategoryText" type="xs:string" minOccurs="0" />
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:choice>
</xs:complexType>
</xs:element>
</xs:schema>
<Category>
<CategoryValue>Case Management</CategoryValue>
<CategoryText>Case Management</CategoryText>
</Category>

[rrflore2]

Can anyone suggest a forum where I could get some help with this issue?

[rrflore2]

I found some help for this problem! The problem was that I was not reassigning the listbox datasource. I change the protected void LoadCategories() to accept a dataset from the add and remove category functions. See code below.

using System;
using System.Data;
using System.Data.SqlClient;
using System.Configuration;
using System.Collections;
using System.IO;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Xml;
 
public partial class _Default : System.Web.UI.Page
{
    DataSet ds = new DataSet();
    XmlDataDocument xmlDataDoc = new XmlDataDocument();
 
 
    protected void Page_Load(object sender, EventArgs e)
    {
 
        if (!Page.IsPostBack)
        {
            //Bind lstCategory to dsXml
            LoadCategories(GetCategoryDs());
 
        }
 
    }
 
    protected void LoadCategories(DataSet dsCategory)
    {
 
        //ds = GetCategoryDs();
 
        DataView dv = dsCategory.Tables["Category"].DefaultView;
        dv.Sort = "CategoryText ASC";
 
        lstCategory.DataSource = dsCategory;
        lstCategory.DataMember = "Category";
        lstCategory.DataTextField = "CategoryText";
        lstCategory.DataValueField = "CategoryValue";
        lstCategory.DataBind();
 
    }
    protected DataSet GetCategoryDs()
    {
        DataSet dsCategory = new DataSet();
        string filepath = Server.MapPath("xml") + "\\Categories.xml"; 
 
        dsCategory = xmlDataDoc.DataSet;
        dsCategory.ReadXml(filepath);
        dsCategory.ReadXmlSchema(filepath);
 
        return dsCategory;
 
    }
 
    protected void btnAddCategory_Click(object sender, EventArgs e)
    {
        if (txtCategroy.Text != "")
        {
 
            ds = GetCategoryDs();
            string filepath = Server.MapPath("xml") + "\\Categories.xml";
 
            DataRow dr = ds.Tables["Category"].NewRow();
            dr["CategoryText"] = txtCategroy.Text;
            dr["CategoryValue"] = txtCategroy.Text;
 
            ds.Tables["Category"].Rows.Add(dr);
 
            ds.WriteXml(filepath, XmlWriteMode.WriteSchema);
 
            //Clear text box and change from xmldatasource to dataset and rebind listbox
            txtCategroy.Text = "";
            LoadCategories(ds);
            lstCategory.DataBind();
 
        }
 
    }
    protected void btnRemoveCategory_Click(object sender, EventArgs e)
    {
 
        if (lstCategory.SelectedItem != null)
        {
 
            ds = GetCategoryDs();
            string filepath = Server.MapPath("xml") + "\\Categories.xml";
 
            DataView dv = ds.Tables["Category"].DefaultView;
            dv.Sort = "CategoryText";
 
            int rowindex = dv.Find(lstCategory.SelectedItem.ToString());
 
            if (rowindex == -1)
                Response.Redirect("Error.aspx");
 
            else
            {
 
                dv.RowFilter = " CategoryText = '" + lstCategory.SelectedItem.ToString() + "'";
                dv.Delete(0);
                ds.WriteXml(filepath, XmlWriteMode.WriteSchema);
 
            }
 
            LoadCategories(ds);
            lstCategory.DataBind();
 
        }
 
    }
}