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C# - Transfer the text of a hyperlink through a session inside a repeater

I want to transfer the text of a hyperlink through a session inside a repeater. But I can not think of the logic to do this. My repeater generates links within that dropdown menu and I want to get the text that appears in the link and pass it to another page Sectors.aspx. This is what I have done so far:
--- edit ---
I want that when the link is clicked, the text that is in the link is passed to the other page. For example, the menu has two links, APPLE and BANANA. When the user clicks APPLE, I want the next page Sectors.aspx to know that the user clicked APPLE and not the other options.
ASPX Page:
<asp:Content ID="BodyContent" ContentPlaceHolderID="MainContent" runat="server">
<div class="dropdown">
<button class="dropbtn">Setor</button>
<div class="dropdown_content">
<asp:Repeater ID="sectors_menu" runat="server">
<ItemTemplate>
<asp:HyperLink id="hyperlink1" NavigateUrl="Sectors.aspx" Text='<%#((System.Data.DataRowView)Container.DataItem)["sector"] %>' runat="server"></asp:HyperLink>
</ItemTemplate>
</asp:Repeater>
</div>
</div>
</asp:Content>
Code Behind
public partial class _Default : System.Web.UI.Page
{
MySqlConnection mysql_connection = new MySqlConnection(ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString);
string mysql_string;
MySqlDataAdapter mysql_data_adapter;
public void Page_Load(object sender, EventArgs e)
{
Sector_label();
}
public void Sector_label()
{
mysql_string = "SELECT * FROM employees GROUP BY sector";
mysql_data_adapter = new MySqlDataAdapter(mysql_string, mysql_connection);
DataTable data_table = new DataTable();
mysql_data_adapter.Fill(data_table);
DataView data_view = new DataView(data_table);
sectors_menu.DataSource = data_view;
sectors_menu.DataBind();
for (int count = 0; count < sectors_menu.Items.Count; count++)
{
var test = (HyperLink)sectors_menu.Items[count].FindControl("hyperlink1");
Session["session_hyperlink"] = test.Text;
// Debug.WriteLine(test.Text);
}
}
}

You could add the text as a parameter of the NavigateUrl:
<ItemTemplate>
<asp:HyperLink id="hyperlink1" NavigateUrl='<%# "Sectors.aspx?sector=" + Server.UrlEncode(((System.Data.DataRowView)Container.DataItem)["sector"]).ToString() %>' Text='<%#((System.Data.DataRowView)Container.DataItem)["sector"] %>' runat="server"></asp:HyperLink>
</ItemTemplate>
Then, Sectors.aspx can retrieve it through the "sector" parameter:
protected void Page_Load(object sender, EventArgs e)
{
string sector = Request.Params["sector"];
}
That id="hyperlink1" parameter looks fishy, though. You don't want all your hyperlinks to have the same ID.

Just replace hyperlink tag with this code ,
<asp:HyperLink runat="server" Navigateurl='<%#"Sectors.aspx?mySector="+ Eval("sector") %>'
Text='<%#((System.Data.DataRowView)Container.DataItem)["sector"] %>' />

Create Unique Buttons Inside Repeater

I have a list of items that are retrieved and can have varying amounts. Because of this, I have a Repeater to create a dynamic amount of rows to display each item in. I need a button in each row that can change some of the properties of the item in the list for that specific row. I'm only able to create the same button for each row in the aspx file which means I have no way to determine which row to change because all of the buttons are the same. See below:
<asp:Repeater runat="server" ID="repeater">
<ItemTemplate>
<li class="list-group-item"><%# Container.DataItem %>
<asp:Button ID="btn" runat="server" />
</li>
</ItemTemplate>
</asp:Repeater>
The list items are displayed with a loop, so i've removed the button from the aspx page and instead tried to create buttons in this loop but they are not displaying.
for (int i = 0; i < listItems.Length; i++)
{
openList.Add("ID: " + item[i]);
repeater.DataSource = openList;
Button btn = new Button();
btn.ID = i.ToString();
repeater.Controls.Add(btn);
repeater.DataBind();
}

Don't worry. The buttons are not the same. The framework will ensure that they are unique. And if you want to know which button was clicked, you can send a CommandArgument to the OnCommand method.
<asp:Repeater runat="server" ID="repeater">
<ItemTemplate>
<li class="list-group-item"><%# Container.ItemIndex %>
<asp:Button ID="btn" runat="server" CommandArgument='<%# Container.ItemIndex %>' OnCommand="btn_Command" />
</li>
</ItemTemplate>
</asp:Repeater>
Code behind
protected void btn_Command(object sender, CommandEventArgs e)
{
//if you need to access the button itself
Button btn = sender as Button;
//get the correct index from the commandargument
Label1.Text = e.CommandArgument.ToString();
}

Firing different linkbuttons in a Repeater and saving the value of each in an arraylist

Im using a repeater to display some products in an online shop for a school project. This is how the front end looks with the repeater
<asp:Repeater ID="Repeater1" runat="server" OnItemCommand="rptList_ItemCommand">
<ItemTemplate>
<span style="float:left; padding:25px;" class="backgrnd">
<asp:ImageButton ID="imgProd" runat="server" style="width:150px; height:150px;" ImageUrl='<%# DataBinder.Eval(Container.DataItem, "productImg")%>' CommandArgument='<%# DataBinder.Eval(Container.DataItem, "productID")%>' CommandName="ViewIndividProd"/><br />
<p style="clear:left;">
<asp:Label ID="lbName" runat="server" Text='<%# DataBinder.Eval(Container.DataItem, "productName")%>' /><br />
<asp:Label ID="lbUnitPrice" runat="server" Text='<%# DataBinder.Eval(Container.DataItem, "unitPrice")%>'/><br />
<asp:Label ID="lbRatings" runat="server" Text=''>Ratings</asp:Label><br />
<asp:LinkButton ID="linkCart" runat="server" CommandArgument='<%# DataBinder.Eval(Container.DataItem, "productID")%>' CommandName="AddToCart">Add to Cart</asp:LinkButton>
</p>
</span>
</ItemTemplate>
</asp:Repeater>
As you can see I've added on the OnItemCommand in the Repeater tag so that this is invoked whenever one of the buttons(image/link) is fired. That works perfectly fine for both commandname AddToCart and ViewIndividProd. However, i want to store the the productid of a specific item that was invoked by the particular button. In my case now, it only stores ONE productid in the arraylist at a time and 'forgets' the productid that was stored previously when another linkbutton is clicked.
Question How do i make it such that everytime a linkbutton in the repeater is fired, it remembers the productid pertaining to the linkbutton that was fired and save these ids into the arraylist?
This is how the back end looks
ArrayList cart = new ArrayList();
protected void rptList_ItemCommand(object sender, RepeaterCommandEventArgs e) {
if (e.CommandName == "ViewIndividProd") {
Session["productID"] = e.CommandArgument.ToString();
Response.Redirect("IndividProduct.aspx");
}
if (e.CommandName == "AddToCart") {
string prodid = e.CommandArgument.ToString();
cart.Add(prodid);
Session["ShoppingCart"] = cart;
Response.Redirect("IndividCat.aspx");
}
msg.Text = "Shopping cart: " + String.Join(",", cart.ToArray());
}
Your feedback would be much appreciated.

You need to understand the Asp.net Page life cycle.
A new instance of your Page object is created on every request.
Values from your input are populated into it.
Your array list is getting recreated every time.
If you want the values to persist, you will have to store your arraylist in the ViewState or the Session
Refer: How to: Save Values in View State
void Page_Load(object sender, EventArgs e)
{
if (ViewState["arrayListInViewState"] != null)
{
PageArrayList = (ArrayList)ViewState["arrayListInViewState"];
}
else
{
// ArrayList isn't in view state, so we need to create it from scratch.
PageArrayList = CreateArray();
}
// Code that uses PageArrayList.
}

We can store comma separated or JSON value in either Session or hidden variable (If you are on the same page and opening new page in different tab then we can use hidden variable also). So every time an button has been click we can append the product id.

ASP.NET Button OnClick within Repeater and LoginView

I'm developing a ASP.NET website with a C# backend. I'm having a problem with how to set an onclick event for buttons that are nested inside of both a loginview and a repeater. The code works fine for displaying all of the other data (anonymous view displays only an error message) but right now the buttons just redirect to the same page and remove the repeater and all contents, whereas they're supposed to run a specific delete function. The repeater, as it is right now, uses an alternatingitem template. If I remove the buttons from the nested controls, they work. I've tried this with buttons, linkbuttons, and imagebuttons. I'd rather use the latter, if possible. Is it possible to assign an Onclick to these buttons if they're nested like this? If not, what approach should I use?
<asp:LoginView ID="LoginLinksView" runat="server" EnableViewState="false">
<AnonymousTemplate>
<asp:Label ID="errorlabel" runat="server"></asp:Label>
</AnonymousTemplate>
<LoggedInTemplate>
<asp:Repeater id="Repeater" runat="server" >
<HeaderTemplate>
<table cellspacing="0" cellpadding="0">
<thead></thead>
</HeaderTemplate>
<ItemTemplate>
<tr class="Repeaterrow">
<!--Additional code here-->
<asp:ImageButton ID="delbutton" runat="server" ImageUrl=
"~/Images/delete.png" Onclick="DeleteOnClick"/>
</tr>
</ItemTemplate>
<AlternatingItemTemplate>
<tr class="Repeaterrow">
<!--Additional code here-->
<asp:ImageButton ID="delbutton" runat="server" ImageUrl=
"~/Images/delete.png" Onclick="DeleteOnClick"/>
</tr>
</AlternatingItemTemplate>
<FooterTemplate>
</table>
</FooterTemplate>
</asp:Repeater>
</LoggedInTemplate>
</asp:LoginView>

Here are the problems with your approach
1- The button issues postback as it should. But you need to put some CommandArgument with to identify "key" or which row you are processing it for.
2- Re Bind your Repeater with source. Below is the sample code for you.
protected void Page_Load(object sender, EventArgs e)
{
BindRepeater();
}
private void BindRepeater()
{
List<int> items = new List<int>();
for (int i = 0; i < 10; i++)
{
items.Add(i);
}
Repeater.DataSource = items;
Repeater.DataBind();
}
protected void DeleteOnClick(object sender, EventArgs e)
{
ImageButton delbutton = (sender as ImageButton);
//1- call your method with passing in delbutton.CommandArgument - it will give you key/ whatever you like
//2- Rebind the Repeater here and that will bind controls again...
BindRepeater();
}
protected void Repeater_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
ImageButton delbutton = (sender as RepeaterItem).FindControl("delbutton") as ImageButton;
if (delbutton != null)
{
delbutton.CommandArgument = (sender as RepeaterItem).ItemIndex.ToString();
}
}
and ASPX Repeater definition would change to
Thanks,
Riz

Problem with a hyperlink

I put a hyperlink inside a datalist..
<ItemTemplate>
<asp:HyperLink ID="HyperLink1" runat="server">'<%# Eval("ThreadTitle") %>'</asp:HyperLink>
<br />
<br />
</ItemTemplate>
I want it to enable it to be pressed so that the datalist event will be triggered and transfer me to another page:
protected void DataList1_SelectedIndexChanged(object sender, EventArgs e)
{
Server.Transfer("AnswerQuestion.aspx?x=" + DataList1.DataKeyField + "&question=" + DataList1.SelectedValue + "&time=" + DateTime.Now);
}
Unfortunately, the link seems to be disabled and I cant press on it to trigger the DataList Selected event..
How can I make the hyperlink active ?

If you want to trigger a selecteditemchaned event use a LinkButton instead of hyperlink.
<asp:DataList ID="DataList1" runat="server"
onselectedindexchanged="DataList1_SelectedIndexChanged">
<ItemTemplate>
<asp:LinkButton ID="sjdj" runat="server" CommandName="Select">
<%# Container.DataItem %></asp:LinkButton>
</ItemTemplate>
</asp:DataList>
In the code behind have
protected void DataList1_SelectedIndexChanged(object sender, EventArgs e)
{
Server.Transfer("~/jjtestjj.aspx?" + DataList1.DataKeyField);
}

why arent you using the Hyperlink as a hyperlink?
You can set the NavigationURL and Text using the OnItemDataBound (or equivalent) event.
this code works with an asp:Repeater:
protected void Row_DataItem(object row, RepeaterItemEventArgs args)
{
if (args.Item.ItemType == ListItemType.AlternatingItem || args.Item.ItemType == ListItemType.Item)
{
var item = (DataItemPOCO)args.Item.DataItem;
var link = (HyperLink)args.Item.FindControl("HyperLink1");
link.Text = item.LinkText;
link.NavigateUrl = item.URL;
}
}