Question

How do I get access to the parent controls of user control in C# (winform). I am using the following code but it is not applicable on all types controls such as ListBox.

Control[] Co = this.TopLevelControl.Controls.Find("label7", true);
Co[0].Text = "HelloText"

Actually, I have to add items in Listbox placed on parent ‘Form’ from a user control.

Answer 1

Description

You can get the parent control using Control.Parent.

Sample

So if you have a Control placed on a form this.Parent would be your Form.

Within your Control you can do

Form parentForm = (this.Parent as Form);

More Information

• MSDN: Control.Parent Property

Update after a comment by Farid-ur-Rahman (He was asking the question)

My Control and a listbox (listBox1) both are place on a Form (Form1). I have to add item in a listBox1 when user press a button placed in my Control.

You have two possible ways to get this done.

1. Use `Control.Parent

Sample

MyUserControl

    private void button1_Click(object sender, EventArgs e)
    {
        if (this.Parent == null || this.Parent.GetType() != typeof(MyForm))
            return;

        ListBox listBox = (this.Parent as MyForm).Controls["listBox1"] as ListBox;
        listBox.Items.Add("Test");
    }

or

2.

• put a property public MyForm ParentForm { get; set; } to your UserControl
• set the property in your Form
• assuming your ListBox is named listBox1 otherwise change the name

Sample

MyForm

public partial class MyForm : Form
{
    public MyForm()
    {
        InitializeComponent();
        this.myUserControl1.ParentForm = this;
    }
}

MyUserControl

public partial class MyUserControl : UserControl
{
    public MyForm ParentForm { get; set; }

    public MyUserControl()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        if (ParentForm == null)
            return;

        ListBox listBox = (ParentForm.Controls["listBox1"] as ListBox);
        listBox.Items.Add("Test");

    }
}