如何在 C# 窗口应用程序中以编程方式创建按钮？

Question

I know that it easy to just drag and drop a button, however a lecturer insists on creating buttons programmatically.

In the Form1_Load method what code should I write to create a simple button?

 private void Form1_Load(object sender, System.EventArgs e)
 {

 }

So that on Load the button would show?

Answer 1

As you said it is Winforms, you can do the following...

First create a new Button object.

Button newButton = new Button();

Then add it to the form inside that function using:

this.Controls.Add(newButton);

Extra properties you can set...

newButton.Text = "Created Button";
newButton.Location = new Point(70,70);
newButton.Size = new Size(50, 100);

Your issue you're running to is that you're trying to set it on Form_Load event, at that stage the form does not exist yet and your buttons are overwritten. You need a delegate for the Shown or Activated events in order to show the button.

For example inside your Form1 constructor,

public Form1()
{
    InitializeComponent();
    this.Shown += CreateButtonDelegate;
}

Your actual delegate is where you create your button and add it to the form, something like this will work.

private void CreateButtonDelegate(object sender, EventArgs e)
{
    Button newButton= new Button();
    this.Controls.Add(newButton);
    newButton.Text = "Created Button";
    newButton.Location = new Point(70,70);
    newButton.Size = new Size(50, 100);
    newButton.Location = new Point(20, 50);
}

Answer 2

on your eventload form put this code

 private void Form1_Load(object sender, EventArgs e)
    {
        Button testbutton = new Button();
        testbutton.Text = "button1";
        testbutton.Location = new Point(70, 70);
        testbutton.Size = new Size(100, 100);
        testbutton.Visible = true;
        testbutton.BringToFront();
        this.Controls.Add(testbutton);

    }

Answer 3

I couldnt manage to create a button. When i write the part of;

this.Controls.Add(testbutton);

i couldnt find the "Controls" part . it has red line under it. Do you know how to fix it?

Answer 4

It's simple :

private void Form1_Load(object sender, System.EventArgs e)
 {
     Button btn1 = new Button();
     this.Controls.add(btn1);
     btn1.Top=100;
     btn1.Left=100;
     btn1.Text="My Button";

 }