form1.vb

简单的VB。net的按钮操作

Public Class Form1
    Inherits System.Windows.Forms.Form

#Region " Windows 窗体设计器生成的代码 "

    Public Sub New()
        MyBase.New()

        '该调用是 Windows 窗体设计器所必需的。
        InitializeComponent()

        '在 InitializeComponent() 调用之后添加任何初始化

    End Sub

    '窗体重写处置以清理组件列表。
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Windows 窗体设计器所必需的
    Private components As System.ComponentModel.IContainer

    '注意：以下过程是 Windows 窗体设计器所必需的
    '可以使用 Windows 窗体设计器修改此过程。
    '不要使用代码编辑器修改它。
    Friend WithEvents TxtGraph As System.Windows.Forms.TextBox
    Friend WithEvents BtnGraph As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.TxtGraph = New System.Windows.Forms.TextBox
        Me.BtnGraph = New System.Windows.Forms.Button
        Me.SuspendLayout()
        '
        'TxtGraph
        '
        Me.TxtGraph.Location = New System.Drawing.Point(24, 24)
        Me.TxtGraph.Multiline = True
        Me.TxtGraph.Name = "TxtGraph"
        Me.TxtGraph.Size = New System.Drawing.Size(152, 56)
        Me.TxtGraph.TabIndex = 0
        Me.TxtGraph.Text = ""
        '
        'BtnGraph
        '
        Me.BtnGraph.Location = New System.Drawing.Point(62, 91)
        Me.BtnGraph.Name = "BtnGraph"
        Me.BtnGraph.TabIndex = 1
        Me.BtnGraph.Text = "绘图"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(208, 126)
        Me.Controls.Add(Me.BtnGraph)
        Me.Controls.Add(Me.TxtGraph)
        Me.Name = "Form1"
        Me.Text = "GraphOnCon"
        Me.ResumeLayout(False)

    End Sub

#End Region


    Private Sub BtnGraph_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnGraph.Click
        Dim g As Graphics
        Dim brushRed As SolidBrush = New SolidBrush(Color.Red)
        Dim brushGreen As SolidBrush = New SolidBrush(Color.Green)
        Dim brushYellow As SolidBrush = New SolidBrush(Color.Yellow)

        '文本框名为TxtGraph;通过调用TxtGraph控件的成员函数CreateGraphics()得到了一个Graphics对象
        g = TxtGraph.CreateGraphics()


        '填充椭圆(格调,起点x,y; 向x方向宽度,向y方向高度)
        '这里起点为(42,2),向x方向宽度28,向y方向高度28
        g.FillEllipse(brushRed, 42, 2, 28, 28)

        g.FillEllipse(brushGreen, 12, 2, 28, 28)
        g.FillEllipse(brushYellow, 72, 2, 28, 28)
    End Sub
End Class