FindControl & Change Textbox to Integer?

Question

Im pretty new to this an FindControl is completely confusing me. Can anyone please tell me what the code should be to change the input from the TextBox: txtamount to an integer called 'increment'. I can't even find the control.. I've tried Ctype, Cint LoginView1.Findcontrol etc with no joy. Any help is appreciated. Here's the Front end followed by the VB Code...

<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent"Runat="Server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent"Runat="Server">

<div style="text-align:center;">

    <asp:LoginView ID="LoginView1" runat="server">
        <AnonymousTemplate>
            <h2>Please <asp:HyperLink ID="HyperLink2" runat="server"         NavigateUrl="~/register-account.aspx" CssClass="boldStyle">REGISTER</asp:HyperLink> or <asp:HyperLink ID="hypLogin" runat="server" CssClass="nyroModal boldStyle" NavigateUrl="~/login2.aspx?page=vipseller">LOG IN</asp:HyperLink></h2>

        </AnonymousTemplate>
        <LoggedInTemplate>
             <h1>Shop Keeper<h1>
             <h2>Enter cash amount being spent or redeemed by customer:</h2>

             <asp:TextBox ID="txtAmount" runat="server" MaxLength="15" TabIndex="8" ></asp:TextBox>
             <br><br>

             <asp:Button ID="btnSpent" runat="server" Text="Spent" TabIndex="10" CssClass="button greyShaded" onclick="AddPoints_Click" />
             <asp:Button ID="btnRedeemed" runat="server" Text="Redeem" TabIndex="10" CssClass="button greyShaded" /><br><br>
        </LoggedInTemplate>
    </asp:LoginView>
</div>
</asp:Content>

VB Code

Protected Sub AddPoints_Click(sender As Object, e As EventArgs)
   dim increment as integer = Cint(LoginView1.FindControl("txtamount"))
   response.write(increment)

I assume you want the integer value of the text of the TextBox. You are currently converting the TextBox itself to an integer. — j.f., Jun 14 '16 at 17:53

Steve · Accepted Answer · 2016-06-14T18:10:01.040

2

FindControl, as the name suggests, tries to find a control and a control is not something that you can convert to an integer

Dim tb As TextBox = DirectCast(LoginView1.FindControl("txtamount"), TextBox)
if tb IsNot Nothing Then
   response.write(CInt(tb.Text))

I suggest also to add a RangeValidator to be sure that the input is made only of valid numbers.

edited Jun 14 '16 at 18:10

answered Jun 14 '16 at 17:53

Steve

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Many thanks for helping. That is giving me error: BC30108: 'Control' is a type and cannot be used as an expression. – Eggybread Jun 14 '16 at 17:57
I am learning myself and know quite a bit of VB now but think I need to do some starter courses to get the basics right first. – Eggybread Jun 14 '16 at 17:58
My fault, declared the variable C# way. – Steve Jun 14 '16 at 18:00
That works.. You're a life saver Steve !! Thanks so much. It's the main part of VB I need to get my head around. Although it works, It's still a bit tricky for me to follow even though I know it's probably easy :-) – Eggybread Jun 14 '16 at 18:05

FindControl & Change Textbox to Integer?

1 Answers1