【代码块】-验证码-绘制到图片显示

整理代码块

代码块整理后存储，供后期使用

Sub showRandomStr()  
  str = String.Empty  
  ' 生成随机数字符串  
  Dim r As Random = New Random()  
  For i = 0 To 4  
    str += r.Next(0, 9).ToString  
  Next   
  
  '画字符串  
  Dim bmp As Bitmap = New Bitmap(120, 20)  
  Dim g As Graphics = Graphics.FromImage(bmp)  
  Dim fonts As String() = {"宋体", "楷体", "仿宋", "草书", "华文行楷"}  
  Dim colors As Color() = {Color.Blue, Color.Green, Color.Red, Color.White, Color.Yellow}  
  For i = 0 To str.Length - 1  
    Dim p As Point = New Point(i * 20 + 10, 0)  
    g.DrawString(str(i).ToString, New Font(fonts(r.Next(0, fonts.Length)), 20), New SolidBrush(colors(r.Next(0, colors.Length))), p)  
  Next   
  '画线  
  For i = 0 To 20  
    g.DrawLine(New Pen(Color.Black), New Point(r.Next(0, bmp.Width), r.Next(bmp.Height)) _  , New Point(r.Next(0, bmp.Width), r.Next(bmp.Height)))  
  Next   
  '画点  
  For i = 0 To 300  
    bmp.SetPixel(r.Next(0, bmp.Width), r.Next(0, bmp.Height), Color.Black)  
  Next   
  pbx.Image = bmp  
End Sub