Count number of checkbox selected

Question

I have a grid with Repeater:

 <asp:Repeater ID="rtInlineBlock" runat="server">
                        <ItemTemplate>

                            <div class="block">
                                <asp:HiddenField ID="idDirectorio" runat="server" Value='<%# Eval("guid") %>' />
                                <asp:HiddenField ID="isFolder" runat="server" Value='<%# Eval("isFolder") %>' />

                                <asp:ImageButton ID="btSend" runat="server" ImageUrl='<%# Eval("imgPath") %>' OnClick="btSend_Click" />

                                <div class="bottom">
                                    <asp:CheckBox ID="check" runat="server"  OnCheckedChanged="check_CheckedChanged" AutoPostBack="true" />
                                    <asp:Label ID="lblNome" runat="server" Text='<%# Eval("xInfo") %>'  />
                                </div>
                            </div>
                        </ItemTemplate>
                    </asp:Repeater>

And my selection event:

protected void check_CheckedChanged(object sender, EventArgs e)
    {
        var cbSend = sender as CheckBox;
        var rtItem = cbSend.Parent as RepeaterItem;

        int cont = 0;
        foreach (var item in rtInlineBlock.Items)
        {

            if (cbSend.Checked)
            {
                cont = cont + 1;
            }
        }

}

I tried that way, but always takes all the checkboxes, I want only the selected.

Answer 1

@Warlock, I really don’t understand why you need to count the Checkboxes every Callback.

If you need to do something that takes into account the selected Checkboxes, the logical thing would be that the event was triggered by an external Button to the Repeater.

But returning the question, you can adapt my method to count the selected Checkboxes from the following template:

protected void check_CheckedChanged(object sender, EventArgs e)
{
    var cont = 0;
    foreach (var rbItem in rtInlineBlock.Items)
    {
        var cbSend = rbItem.FindControl("check") as CheckBox;
        if (cbSend.Checked)
        {
            cont++;
        }
    }
}

Answer 2

You have a logic error there, cbSend is always the same object inside the loop, you are doing this:

 int cont = 0;
 if (cbSend.Checked)
 {
       cont = rtInlineBlock.Count;
 }

The difference is I made no loop.

If you want to re-check the checkboxes whenever someone checks / deselect you need to pick item and find the checkbox inside it and check that checkbox.

I don’t think this is a good solution, you could work with a variable that maintains status and every click add or subtract based on the value of checked.

It is an exchange, memory for processing, and in this case the cost of memory is too small to justify this repeated processing, which only worsens the more items enter the Reset.

I will put an example (I do not know if it will run, if it does not run put the error that I fix):

protected void check_CheckedChanged(object sender, EventArgs e)
{
        var cbSend = sender as CheckBox;

        // Acho que faltava um convert aqui... null é zero.
        int cont = Convert.ToInt32(Session["cont"]);

        Session["cont"] = cont = cbSend.Checked ? cont + 1 : cont -1;

        // Prossiga com o que você quer fazer
}

Worth saying in the Page_Load initialize the Session["cont"] = 0 (if not postback) to prevent strange behavior from occurring while browsing the site.