WebPart-Button Click

Question

I have a table called Links. two stored Procedures called sp_InsertLinks, sp_GetLinks.

I have simple webpart which takes two parameters and adds it the SQL Table call Links.

In The first Interface it displays the list of values from the database and a Button to ADD List.

When I click on the Link it displays next interface, where I can add txtbox for Link Name and Txtbox for Link URL.

And When I submit this The page is loading in the sequence of events of normal sharepoint lifecycle.

And I am unable to add the new links into the page because the button click method never gets fired.

Could any one have a look at this please?

The Code is :

  using System;
using System.Runtime.InteropServices;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Serialization;
using System.Text ;
using System.Data ;
using System.Data.SqlClient;
using System.Drawing;
using Microsoft.SharePoint;
using Microsoft.SharePoint.WebControls;
using Microsoft.SharePoint.WebPartPages;

namespace ContextMenuOptionsUsingJQuery
{
    [Guid("7a3a52d4-9ad6-44b2-b96f-852da1a95371")]
    public class ContextMenuOptionsUsingJQuery : System.Web.UI.WebControls.WebParts.WebPart
    {

        SqlConnection con;
        SqlCommand cmd;
        SqlDataReader dr;
        string Con_string = string.Empty;
        Button btnAddLink;
        Button btnAddNewLink;
        StringBuilder outputDisplay;
        TextBox txtLink;
        TextBox txtLinkUrl;
        Label lblDisplay = new Label();

        public ContextMenuOptionsUsingJQuery()
        {

        }



         protected override void CreateChildControls()
        {
            try
            {

                // Getting the Connection 

                ConnectionMethod();

                // Calling the Appropraite Method or stored Procedures

                RefreshData();



                // Adding a New Link though the button

                    btnAddLink = new Button();
                    btnAddLink.Text = "Add Link";
                    btnAddLink.Click += new EventHandler(btn_AddLink);

                    //New item

                    Controls.Add(btnAddLink);



            }
            catch (Exception e)
            {
                Label l = new Label();
                l.Text = e.StackTrace;
                Controls.Add(l);
            }         
        }



        // Button Add Link
        private void btn_AddLink(Object sender, EventArgs e)
        {
            Controls.Clear();
            btnAddNewLink = new Button();
            txtLink = new TextBox();
            txtLinkUrl = new TextBox();
            Controls.Add(txtLink);
            Controls.Add(txtLinkUrl);                
            btnAddNewLink.Text = "ADD NEW Link";
            btnAddNewLink.Click += new EventHandler(btnAddNewLink_Click);
            Controls.Add(btnAddNewLink);

        }
        private void btnAddNewLink_Click(Object sender, EventArgs e)
        {
            int i;
            try
            {
                ConnectionMethod();
                cmd.CommandText = "sp_InsertLinks";
                cmd.CommandType = CommandType.StoredProcedure;
                SqlParameter paramLinkName = new SqlParameter("@LinkName", SqlDbType.VarChar, 50);
                SqlParameter paramLinkUrl = new SqlParameter("@LinkUrl", SqlDbType.VarChar, 50);
                paramLinkName.Direction = ParameterDirection.Input;
                paramLinkUrl.Direction = ParameterDirection.Input;
                paramLinkName.Value = txtLink.Text.ToString();
                paramLinkUrl.Value = txtLinkUrl.Text.ToString();
                cmd.Parameters.Add(paramLinkUrl);
                cmd.Parameters.Add(paramLinkName);
                i = cmd.ExecuteNonQuery();
                con.Close();
                ConnectionMethod();
                RefreshData();
            }
            catch (Exception exp)
            {
                Label l = new Label();
                l.Text = exp.StackTrace;
                Controls.Add(l);
            }
            finally
            {
                con.Close();
            }         

        }
        private void RefreshData()
        {
            cmd.CommandText = "sp_GetLinks";
            cmd.CommandType = CommandType.StoredProcedure;
            dr = cmd.ExecuteReader();

            outputDisplay = new System.Text.StringBuilder();
            outputDisplay.AppendLine("<br/>");

            // Fetching the Data from the Datareader object

            while (dr.Read())
            {
                outputDisplay.AppendLine("<a href=" + dr[0].ToString() + ">" + dr[1] + "</a>" + "<br/><br/>");
            }
            con.Close();
            outputDisplay.AppendLine("<br/> <br/>");
            lblDisplay.Text = outputDisplay.ToString();
            Controls.Add(lblDisplay);

        }


        // Method to get the Connection

        public void ConnectionMethod()
        {
            con = new SqlConnection();
            cmd = new SqlCommand();
            Con_string = "Data Source=servername;Initial Catalog=HariVMTest;Integrated Security=True";
            con.ConnectionString = Con_string;
            con.Open();
            cmd.Connection = con;
        }
    }
}

Thank you

Hari

Answer 1

I would nearly always recommend creating all your controls in CreateChildControls()

Then you should use the Visible property to show and hide the controls as needed.

The code would then look something like this:

public class ContextMenuOptionsUsingJQuery : System.Web.UI.WebControls.WebParts.WebPart {

    Button btnAddLink;
    Button btnAddNewLink;

    protected override void CreateChildControls() {
        btnAddLink = new Button();
        btnAddLink.Text = "Add Link";
        btnAddLink.Click += new EventHandler(btn_AddLink);
        Controls.Add(btnAddLink);    

        btnAddNewLink.Text = "ADD NEW Link";
        btnAddNewLink.Click += new EventHandler(btnAddNewLink_Click);
        btnAddNewLink.Visible = false;
        Controls.Add(btnAddNewLink);
    }

    private void btn_AddLink(Object sender, EventArgs e) {
        btnAddLink.Visible = false;
    }

    private void btnAddNewLink_Click(Object sender, EventArgs e) {

    }
}

If you do it this way, your events will more often than not, fire correctly.

Answer 2

i think you need to just add : // Adding a New Link though the button btnAddLink = new Button(); btnAddLink.Text = "Add Link"; btnAddLink.Click += new EventHandler(btn_AddLink);

before connectionmethod in createchildcontrol()

hope this works.