本文所述為VB實現鼠標繪圖的實例，該實例實現線條顏色和線寬可自設，當按下鼠標按鍵時繪圖開始并記錄最初的起點，如果不是處在繪圖狀態則退出該過程，如果處在繪圖狀態則從起點到目前鼠標所在點繪制直線，然后將當前鼠標所在點作為新的起點，當釋放鼠標按鍵時繪圖結束。
具體的功能代碼如下：
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VERSION 5.00Object = "{F9043C88-F6F2-101A-A3C9-08002B2F49FB}#1.2#0"; "comdlg32.ocx"Begin VB.Form Form1 Caption = "鼠標繪圖" ClientHeight = 6420 ClientLeft = 60 ClientTop = 345 ClientWidth = 7710 LinkTopic = "Form1" ScaleHeight = 6420 ScaleWidth = 7710 StartUpPosition = 3 '窗口缺省 Begin VB.CommandButton Command2 Caption = "清除" Height = 495 Left = 5640 TabIndex = 7 Top = 1440 Width = 1335 End Begin VB.Frame Frame1 Caption = "線寬" Height = 2655 Left = 5520 TabIndex = 2 Top = 2880 Width = 1935 Begin VB.OptionButton Option4 Caption = "8" Height = 495 Left = 240 TabIndex = 6 Top = 1800 Width = 1215 End Begin VB.OptionButton Option3 Caption = "4" Height = 375 Left = 240 TabIndex = 5 Top = 1320 Width = 1335 End Begin VB.OptionButton Option2 Caption = "2" Height = 375 Left = 240 TabIndex = 4 Top = 840 Width = 1095 End Begin VB.OptionButton Option1 Caption = "1" Height = 255 Left = 240 TabIndex = 3 Top = 480 Value = -1 'True Width = 1335 End End Begin VB.CommandButton Command1 Caption = "設置顏色" Height = 495 Left = 5640 TabIndex = 1 Top = 600 Width = 1215 End Begin MSComDlg.CommonDialog CommonDialog1 Left = 4200 Top = 3840 _ExtentX = 847 _ExtentY = 847 _Version = 393216 End Begin VB.PictureBox Picture1 Height = 5535 Left = 480 ScaleHeight = 5475 ScaleWidth = 4515 TabIndex = 0 Top = 480 Width = 4575 EndEndAttribute VB_Name = "Form1"Attribute VB_GlobalNameSpace = FalseAttribute VB_Creatable = FalseAttribute VB_PredeclaredId = TrueAttribute VB_Exposed = FalseDim x1 As Integer '起點X坐標Dim y1 As Integer '起點Y坐標Dim x2 As Integer '終點點X坐標Dim y2 As Integer '終點Y坐標Dim flag As Boolean '繪圖標志'設置線的顏色Private Sub Command1_Click() On Error Resume Next CommonDialog1.CancelError = True CommonDialog1.DialogTitle = "顏色" CommonDialog1.ShowColor If Err <> 32755 Then Picture1.ForeColor = CommonDialog1.Color End IfEnd Sub'清除Picture1中的圖形Private Sub Command2_Click() Picture1.ClsEnd Sub'設置線寬Private Sub Option1_Click() Picture1.DrawWidth = 1End SubPrivate Sub Option2_Click() Picture1.DrawWidth = 2End SubPrivate Sub Option3_Click() Picture1.DrawWidth = 4End SubPrivate Sub Option4_Click() Picture1.DrawWidth = 8End SubPrivate Sub Form_Load() Picture1.Scale (0, 0)-(400, 400) flag = FalseEnd SubPrivate Sub Picture1_MouseDown(Button As Integer, Shift As Integer, _X As Single, Y As Single)'當按下鼠標按鍵時繪圖開始并記錄最初的起點 flag = True x1 = X y1 = YEnd SubPrivate Sub Picture1_MouseMove(Button As Integer, Shift As Integer, _X As Single, Y As Single)'如果不是處在繪圖狀態則退出該過程'如果處在繪圖狀態則從起點到目前鼠標所在點繪制直線'然后將當前鼠標所在點作為新的起點 If flag = False Then Exit Sub End If If flag = True Then x2 = X y2 = Y Picture1.Line (x1, y1)-(x2, y2) x1 = x2 y1 = y2 End IfEnd SubPrivate Sub Picture1_MouseUp(Button As Integer, Shift As Integer, _X As Single, Y As Single)'當釋放鼠標按鍵時繪圖結束 flag = FalseEnd Sub |
程序中備有較為詳細的注釋，相信讀者不難理解，讀者可以根據自己的喜好對該程序進行修改，使之更加完善！
