vb.net - 按下按钮时创建一条线

Question

我想“实时”制作一个绘图程序。我的表单中有两个文本框和一个按钮。我想在文本框中输入两个值，按下按钮并画线。

我试图从b_Click（b是按钮）调用，Form_paint但不知道如何处理sender和e参数。

有没有办法做到这一点？

Public Class Form1
Dim a, c, d, e As Integer



Private Sub Form1_Paint(sender As Object, e As PaintEventArgs) Handles Me.Paint
    Dim pen As New Pen(Color.FromArgb(255, 0, 0, 0))
    e.Graphics.DrawLine(pen, a, c, 300, 100)
End Sub

Private Sub b_Click(sender As Object, e As EventArgs) Handles b.Click
    a = t1.Text
    c = t2.Text
    Form1_Paint(0,??)

End Sub

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    a = 0
    c = 0
  End Sub
  End Class

Answer 1

您应该调用 的Refresh方法，而Form不是自己调用事件处理程序。该方法最终将调用Paint事件及其处理程序。

Private Sub b_Click(sender As Object, e As EventArgs) Handles b.Click
    a = t1.Text
    c = t2.Text

    Refresh()
End Sub