从动态创建的文本框和复选框中获取价值

Question

i write the following code to create code

Dim i, x, y As Integer
    x = 30
    y = 25
    i = 0
    For i = 0 To dt1.Rows.Count - 1
        Dim chk As New CheckBox()
        chk.Text = dt1.Rows(i)(0)
        chk.Location = New Point(x, y)
        chk.Font = fnt
        chk.Width = 450
        chk.ForeColor = Color.White

        Me.Panel1.Controls.Add(chk)
        chk.Name = "chk" & Convert.ToString(i)
        Dim txt As New TextBox
        txt.Location = New Point(x, y + 23)
        txt.Font = fnt
        txt.Multiline = True
        txt.Height = 46
        txt.Width = 400
        Me.Panel1.Controls.Add(txt)
        txt.Name = "txt" & Convert.ToString(i)
        y = y + 69

i want to retrive the textvalue of checkbox whose checked property is true and respective textbox at a buttonclick event. Problem is in finding the controls and their textvalue. any one can help?Thanks in Advance.dt1 is datatable .For window form application

Answer 1

Where is that code in the life cycle? It should be before Page_Load in order to get the controls values later. You can give it an Id like

 chk.ID = myId;

To get the value you can write something like this

 CheckBox cb  =(CheckBox)Page.FindControl(myId);

Answer 2

Have you tried looping through the controls? Something like below:

    Dim ctrlName As String = String.Empty
    For Each ctrl As Control In Me.Controls
        If TypeOf ctrl Is CheckBox Then
            Dim chk As CheckBox = CType(ctrl, CheckBox)

            If chk.Checked Then
                ctrlName = chk.Name.Replace("chk", "txt")
            End If
        ElseIf TypeOf ctrl Is TextBox AndAlso ctrl.Name = ctrlName Then
            Dim txt As TextBox = CType(ctrl, TextBox)
            Dim val As String = txt.Text
            ctrlName = String.Empty
        End If
    Next

I haven't tested this, just an idea.

Answer 3

Create a new VB Windows Form application and add a button then replace the code of the form with this code:

Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim txt As New TextBox
        txt.Name = "myText"
        txt.Left = Me.Width / 2
        txt.Top = Me.Height / 2
        txt.Text = "here is my text"

        Me.Controls.Add(txt)              'This will add the dynamically created object

        Dim anotherObj As TextBox = Me.Controls.Item("myText")    'because we know the name of the object we created before, we can retreive it back

        MsgBox(anotherObj.Text)      'and we can also get the text we assigned earlier.


    End Sub


End Class

The last 2 lines can be put inside another Sub() and you would still have the same result.

Answer 4

    Dim txtbranchname1 As TextBox
    Private boxes(1) As TextBox

    newbox = New TextBox
    newbox.Size = New Drawing.Size(100, 20)
    newbox.Name = "txtBranchName"
    newbox.TabIndex = 1
    newbox.Dock = DockStyle.Fill
    AddHandler newbox.TextChanged, AddressOf TextBox_TextChanged
    AddHandler newbox.KeyDown, AddressOf TextBox_Keydown
    Me.TableLayoutPanel1.Controls.Add(newbox)
    txtbranchname1 = Me.TableLayoutPanel1.Controls.Item("txtBranchName")

    'Enter the value to textbox on runtime
    MsgBox( txtbranchname1.Text)

    'assign value to textbox
    txtbranchname1.Text = "Something"

Answer 5

Don't forget you must re-create all dynamic controls on postback

Your Page is just a class remember and it is instantiated once per request, if it doesn't recreate these controls as well as the associated handlers on the postback request then you won't get anything happen..

You need to recreate these controls prior to Page_Load , you can do this in Page_Init or override the CreateChildControls method.