VB.Net 2008 如何以颜色填充

Question

已知PICTUREBOX内一个封闭区域内的一个点，坐标是(X，Y)，如何以某一种颜色填充这个区域
我用的是下面的方法：
建立一个窗体，在其中加一个PICTUREBOX1，加如下代码

    Private Declare Function CreateSolidBrush Lib "gdi32" (ByVal crColor As Integer) As Integer
    Private Declare Function SelectObject Lib "gdi32" (ByVal hdc As Integer, ByVal hObject As Integer) As Integer
    Private Declare Function ExtFloodFill Lib "gdi32" (ByVal hdc As Integer, ByVal X As Integer, ByVal Y As Integer, ByVal crColor As Integer, ByVal wFillType As Integer) As Integer
    Private Declare Function GetPixel Lib "gdi32" (ByVal hdc As Integer, ByVal X As Integer, ByVal Y As Integer) As Integer

 

  Private Sub Picturebox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Picturebox1.MouseDown
       
        Dim g As Graphics = Me.Picturebox1.CreateGraphics()
        Dim mBrush As Integer
        mBrush = CreateSolidBrush(QBColor(3))
        SelectObject(g.GetHdc, mBrush)
        g.ReleaseHdc()
        Dim a As Integer
        a = GetPixel(g.GetHdc, e.X, e.Y)
        g.ReleaseHdc()
        ExtFloodFill(g.GetHdc, e.X, e.Y, a, 1)
        g.ReleaseHdc()
    End Sub

在PICTUREBOX1中放置一个图片，运行以上程序，不管QBColor(3)是如何变化，都是以白色填充，速度倒是不慢，请大家看看，有什么地方不对

微软也没有说在net中不好用API呀，可这样用为何就得不到结果呢，这个老盖!!!
如果不用API，那么有什么好的方法么，建议速度不能太慢了

Answer 1

我建议你在  .NET  中还是用  .NET  里面的各种方法吧

2008里面是原生支持 solidbrush  的。

 

关于你的这个应用我建议你看看《 application=code + markup》的第三章（如果我没有记错的话。就是将brush的那一章）

Answer 2

Code Snippet

 

Private Sub PictureBox1_MouseDown(ByVal sender As System.Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseDown
        Dim g As Graphics = Me.PictureBox1.CreateGraphics()
        Dim mBrush As Integer

        Dim hdc As Integer

        hdc = g.GetHdc
        mBrush = CreateSolidBrush(QBColor(3))
        SelectObject(hdc, mBrush)

        Dim a As Integer

        a = GetPixel(hdc, e.X, e.Y)

        ExtFloodFill(hdc, e.X, e.Y, a, 1)
        g.ReleaseHdc()

    End Sub