Bind dynamically items in dropdownlists

In this tutorial I will show you how to bind items dynamically in dropdownlist.

in this example, i have used hyperlinks and bind the selected link in a single dropdownlist
I have used query string  for passing the value in the dropdownlist to show what items to be displayed.
you can also use session variables and also cookies for binding items on the list.

this is WebForm1.aspx

protected void Page_Load(object sender, EventArgs e)
        {
            createNavUrls();
        }
        private void createNavUrls()
        {
         
                HyperLink1.NavigateUrl = @"WebForm2.aspx?Option=1";
           
                HyperLink2.NavigateUrl = @"WebForm2.aspx?Option=2";
         
                HyperLink3.NavigateUrl = @"WebForm2.aspx?Option=3";
        }

this piece of code shows, when the page load, the code will call the createNavUrls(), that adds the navigate url links and shows the query string,, upon selecting on the links it has corresponding values,1,2,3 and the query string name is "Option".

WebForm2.aspx

 protected void Page_Load(object sender, EventArgs e)
        {
            filllist(Convert.ToInt32(Request.QueryString["Option"]));
        }
        private void filllist(int option)
        {
            ddlOptions.Items.Clear();
            if (option == 1)
            {
                ddlOptions.Items.Add("a1");
                ddlOptions.Items.Add("a2");
                ddlOptions.Items.Add("a3");
            }
            else if (option == 2)
            {
                ddlOptions.Items.Add("b4");
                ddlOptions.Items.Add("b5");
                ddlOptions.Items.Add("b6");
            }
            else if (option == 3)
            {
                ddlOptions.Items.Add("c7");
                ddlOptions.Items.Add("c8");
                ddlOptions.Items.Add("c9");
            }
        }

on the other hand, the second page will load, the selected hyperlink's value,

on the page load , the Request.QueryString["Option"], this will read the value given by the 1st page,
then on the method fill,  this will add the items that is selected on the desired input.

here is the sample url of the page.
"http://localhost:56594/WebForm2.aspx?Option=1"

Option is the querystring name and 1 is the value


i hope this code helps.

Adding table to a session

On this post I will show you ,how to add a table to a session and even add a new record, just like a Shopping cart in online shopping websites.

Here is a sample code for adding a table to a session and then rebinding it just like in shopping carts

private void GetData()
{
     try
        {
        DataRow[] dr = null;        if (ViewState["SelectedRecords"] != null)
       {
            dt = (DataTable)ViewState["SelectedRecords"];
       }
       else
       {
            dt = CreateDataTable();    1:
        }

2
CheckBox chkAll = (CheckBox)gvAll.HeaderRow.Cells[0].FindControl("chkAll");
for (int i = 0; i < gvAll.Rows.Count; i++)
{
if (chkAll.Checked)
{
dt = AddRow(gvAll.Rows[i], dt);
}
else
{
CheckBox chk = (CheckBox)gvAll.Rows[i].Cells[0].FindControl("chk");
if (chk.Checked)
{
dt = AddRow(gvAll.Rows[i], dt);
}
else
{
dt = RemoveRow(gvAll.Rows[i], dt);
}
}
}

3.
ViewState["SelectedRecords"] = dt;
dtall = dt.Copy();
Session["CombineRecord"] = dtall;
}
catch (Exception ex)
{
}

this is your main method on how to add or remove items in your datatable, in this example I bound it to a gridview, which have a checkbox for adding or deleting items, this depends on the button clicked

1: means create a datatable
here is the code for creating a datatable

private DataTable CreateDataTable()
{
DataTable dt = new DataTable();
dt.Columns.Add("ItemCode");
dt.Columns.Add("ItemDesc");
dt.AcceptChanges();
return dt;
}

2: this part shows what is the behavior if the checkbox is selected and what button is clicked, either add or remove, 

3: this part shows after selecting after modifying the datatable, you will then pass it to the viewstate named selectedrecords to hold it,

then dtall=dt.copy(); means that all records in the datatable dt is copied and moved to datatable named dtall

where dtall will either have an existing record or a new record

then pass dtall datatable to a session variable so that it will not be disposed after

After this,

private void BindSecondaryGrid()
{
gvCart.DataSource = (DataTable)Session["CombineRecord"];
gvCart.DataBind();
}

convert to datatable the session variable and bind it to your gridview.

This summarizes the passing of values to a session just like in Shopping cart

Mt. Pulag December Climb

Feel the Coldness in Mt. Pulag this December 21-24,as we will climb this mountain on the said date
plus be ware of the fees
this is just baguio-pulag-baguio trip
Guide - 100/head
Jeepney -9k roundtrip

For those who wants to join this adventure, you may put your comment guys,
Check your sched now as i will be updatting this post guys.

Thanks.

Manabu Peak Night Trek

Guys, here is the Itinerary for the Manabu peak Night trek, that will happen on Oct 5-6 2012, but first here is the details of manabu peak

This peak is a part of Malipunyo mountain range, located in Sto. Tomas Batangas, its peak is marked by a white cross, and its trail is like a rosary, basically this mountain is for beginners and it has an easy trail.

below are the description of this peak

 Jump - off point :  Sulok, Brgy. Sta Cruz, Sto. Tomas

 LLA: 13.9777°, 121.2413°, 760 MASL

Days required / Hours to summit: 1 day / 1-2 hours

Specs: Minor climb, Difficulty 2/9, Trail class 1-2

Itinerary:

1800H : Robinsons Pala pala

1930H:: Fiesta mall Lipa, take trike to Sulok, brgy Sta Cruz

2000H: ETA Jump-off

2015H start Trek, Grotto Trail

2115H rest Grotto

2130H resume trek

2230H ETA Summit, Set up Camp , Socials

0030H Lights out

0600H Wake up Call , Breakfast , Explore Summit, picture taking

0900H break camp prepare , descent

1100H Jump off point, take a shower

1200H ETD to Fiesta mall

1300H fiesta mall , lunch

1500H Pala pala

1600H Home

For those who wants to join this adventure, you may put your comment guys

Thanks.

ASP.net Popup Window

On this post, i will give you a code snippet on how you can have a small popup window in your web application using asp.net

first what is a popup window, a popup window is just a small browser that shows some detailed information and often times ads, generally this new browser window is used for advertisements.

with us developers we can use this small popup for showing and minimizing file size, and even the whole page size, for showing what we need to tell the users.

basically popup window code is done through java script using
this code

window.open( URL, windowName[, windowFeatures] );

and since I am using c# in asp.net I use this code for the popup window

LinkButton1.Attributes.Add("onclick","window.open('Users.aspx','','height=300,width=300');return false");

on this code snippet , I have used a link button to open a new popup window, just put this on the page_load() event, and no need to have an event for LinkButton1_click().

i hope this helps, this is useful when you want to show a little information that needs less design and coding.



On my next post I will tell you how to pass values in different web pages, since web application is different in windows application. If you have suggestions and comment you can post it here. Thanks.

How to connect to a Database

Here is a sample code of how to connect to a database

this code is for microsoft access 2003

Imports system.Data.OleDb
Module Module1
    Public dbpath As String = Application.StartupPath + "\dbBilling.mdb"
    Public cnstring = "Provider = Microsoft.Jet.Oledb.4.0;Data Source =" & dbpath
    Public con As New OleDbConnection(cnstring)
End Module

sample Login in VB.net 2008

after a long long time of no post, here is a sample of login program in vb.net

this program have still bugs , and if you found one, post it here. Thanks


Private Sub OK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles OK.Click
        Dim ds As DataSet = New DataSet()
        Dim dr As OleDbDataReader
        Dim da As OleDbDataAdapter = New OleDbDataAdapter
        Try
            con.Open()
            Dim dc As OleDbCommand = New OleDbCommand("Select * From UserAccounts ", con) 
            dr = dc.ExecuteReader()
            With dr
                If .HasRows Then
                    While .Read()
                        If (.Item("UserName").ToString = UsernameTextBox.Text) And (.Item("Password").ToString                          = PasswordTextBox.Text) Then
                            Dim a As String = .Item("UserName").ToString
                            Dim a1 As String = .Item("Password").ToString
                            Form1.Show()
                            .Close()
                            Exit While
                        End If
                    End While
                    Dim b As String = .Item("UserName").ToString
                    Dim b1 As String = .Item("Password").ToString
                    MsgBox("Username or Password is Incorrect", MsgBoxStyle.Critical + MsgBoxStyle.OkOnly)
                    UsernameTextBox.Text = ""
                    PasswordTextBox.Text = ""            
                End If
            End With
            con.Close()
        Catch ex As Exception
        End Try
        con.Close()
    End Sub