User Control vs. Windows Form

What开发者_JAVA技巧 is the difference between a user control and a windows form in Visual Studio - C#?

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Put very simply:

User controls are a way of making a custom, reusable component. A user control can contain other controls but must be hosted by a form.

Windows forms are the container for controls, including user controls. While it contains many similar attributes as a user control, it's primary purpose is to host controls.

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They have a lot in common, they are both derived from ContainerControl. UserControl however is designed to be a child window, it needs to be placed in a container. Form was designed to be a top-level window without a parent.

You can actually turn a Form into a child window by setting its TopLevel property to false:

public partial class Form1 : Form {
    public Form1() {
        InitializeComponent();
        var child = new Form2();
        child.TopLevel = false;
        child.Location = new Point(10, 5);
        child.Size = new Size(100, 100);
        child.BackColor = Color.Yellow;
        child.FormBorderStyle = FormBorderStyle.None;
        child.Visible = true;
        this.Controls.Add(child);
    }
}

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A windows form is a container for user controls.

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The biggest difference is form.show gives a different window while usercontrol doesnt have feature like popping up without a parent. Rest things are same in both the controls like beind derived from Scrollablecontrol.

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A User Control is a blank control, it's a control that's made up of other controls. Building a user control is similar to building a form. It has a design surface, drag and drop controls onto the design surface, set properties, and events. User controls can consolidate UI and code behind. User controls can only be used in the project where they're defined.