求解一元二次方程的VB源代码(可以求共轭复根).doc

VERSION 5.00Begin VB.Form Form1 Caption = 求解一元二次方程 ClientHeight = 3360 ClientLeft = 555 ClientTop = 1155 ClientWidth = 5760 KeyPreview = -1 True LinkTopic = Form1 ScaleHeight = 3360 ScaleWidth = 5760 Begin VB.CommandButton Command2 Caption = 清 空(F2) Height = 375 Left = 3480 TabIndex = 12 Top = 2760 Width = 1695 End Begin VB.CommandButton Command1 Caption = 运 算(F1) Height = 375 Left = 600 TabIndex = 11 Top = 2760 Width = 1695 End Begin VB.TextBox Text3 BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 4200 TabIndex = 6 Top = 720 Width = 1335 End Begin VB.TextBox Text2 BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 2400 TabIndex = 5 Top = 720 Width = 1335 End Begin VB.TextBox Text1 BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 480 TabIndex = 4 Top = 720 Width = 1335 End Begin VB.Label Label10 BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 615 Left = 600 TabIndex = 14 Top = 1680 Visible = 0 False Width = 5055 End Begin VB.Label Label9 Caption = x= BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 120 TabIndex = 13 Top = 1680 Visible = 0 False Width = 375 End Begin VB.Label Label8 BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 615 Left = 600 TabIndex = 10 Top = 2040 Width = 5055 End Begin VB.Label Label7 BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 615 Left = 600 TabIndex = 9 Top = 1320 Width = 5055 End Begin VB.Label Label6 Caption = x2= BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 120 TabIndex = 8 Top = 2040 Width = 375 End Begin VB.Label Label5 Caption = x1= BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 120 TabIndex = 7 Top = 1320 Width = 375 End Begin VB.Label Label4 Caption = c: BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 3960 TabIndex = 3 Top = 720 Width = 255 End Begin VB.Label Label3 Caption = b: BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 2040 TabIndex = 2 Top = 720 Width = 255 End Begin VB.Label Label2 Caption = a: BeginProperty Font Name = 宋体 Size = 10.5 Charset = 134 Weight = 400 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty Height = 375 Left = 240 TabIndex = 1 Top = 720 Width = 240 End Begin VB.Label Label1 Caption = 求解一元二次方程 BeginProperty Font Name = 隶书 Size = 15.75 Charset = 134 Weight = 700 Underline = 0 False Italic = 0 False Strikethrough = 0 False EndProperty ForeColor = &H00800000& Height = 375 Left = 1560 TabIndex = 0 Top = 180 Width = 2850 EndEndAttribute VB_Name = Form1Attribute VB_GlobalNameSpace = FalseAttribute VB_Creatable = FalseAttribute VB_PredeclaredId = TrueAttribute VB_Exposed = FalsePrivate Sub Form_load()Command1.Caption = 运 算(F1) 这两句代码是防止此程序在其他电脑上运行时按钮上的字幕只显示第一个字。Command2.Caption = 清 空(F2)End SubPrivate Sub Command1_Click()Dim a, b, c, d, x, x1, x2, realpart, imagpart As Double 若将x1,x2,x定义为String，则当修复-1x1(或x2或x)0或0x1(或x2或x) 0 Then x1 = (-b + Sqr(d) / (2 * a) x2 = (-b - Sqr(d) / (2 * a) If x1 0 And Left(Str(x1), 1) = . Then 当0x11时，显示出小数点前的0（在VB的默认条件下，整数部分的“0”不显示）。 x1 = 0 & x1 这里采用字符串拼接的方法解决这一问题 End If If x1 0 And Mid(Str(x1), 2, 1) = . Then 当-1x1 0 And Left(Str(x2), 1) = . Then 同上。 x2 = 0 & x2 End If If x2 0 And Left(Str(x), 1) = . Then 同上。 x = 0 & x End If If x 0 And Mid(Str(x), 2, 1) = . Then x = -0 & Abs(x) End If Label5.Visible = False Label6.Visible = False Label7.Visible = False Label8.Visible = False Label9.Visible = True Label10.Visible = True Label10.Caption = x End If If d O And Left(Str(realpart), 1) = . Then If Abs(imagpart) = 1 Then Label7.Caption = 0 & Str(realpart) & +i Label8.Caption = 0 & Str(realpart) & -i Else If Left(Str(Abs(imagpart), 1) = . Then Label7.Caption = 0 & Str(realpart) & + & Format(Abs(imagpart), 0.#) & i Label8.Caption = 0 & Str(realpart) & - & Format(Abs(imagpart), 0.#) & i Else Label7.Caption = 0 & Str(realpart) & + & Str(Abs(imagpart) & i Label8.Caption = 0 & Str(realpart) & - & Str(Abs(imagpart) & i End If End If Else If realpart 0 And Mid(Str(realpart), 2, 1) = . Then If Abs(imagpart) = 1 Then Label7.Caption = -0 & Str(Abs(realpart) & +i Label8.Caption = -0 & Str(Abs(realpart) & -i Else If Left(Str(Abs(imagpart), 1) = . Then Label7.Caption = -0 & Str(Abs(realpart) & + & Format(Abs(imagpart), 0.#) & i Label8.Caption = -0 & Str(Abs(realpart) & - & Format(Abs(imagpart), 0.#) & i Else Label7.Caption = -0 & Str(Abs(realpart) & + & Str(Abs(imagpart) & i Label8.Caption = -0 & Str(Abs(realpart) & - & Str(Abs(imagpart) & i End If End If Else If Abs(imagpart) = 1 Then Label7.Caption = Str(Abs(realpart) & +i Label8.Caption = Str(Abs(realpart) & -i Else If Left(Str(Abs(imagpart), 1) = . Then Label7.Caption = Str(Abs(realpart) & + & Format(Abs(imagpart), 0.#) & i Label8.Caption = Str(Abs(realpart) & - & Format(Abs(imagpart), 0.#) & i Else Label7.Caption = Str(Abs(realpart) & + & Str(Abs(imagpart) & i Label8.Caption = Str(Abs(realpart) & - & Str(Abs(imagpart) & i End If End If End If End If End If End IfEnd IfEnd SubPrivate Sub Command2_Click()Text1.Text = Text2.Text = Text3.Text = Label7.Caption = Label8.Caption = Label5.Visible = TrueLabel6.Visible = TrueLabel7.Visible = TrueLabel8.Visible = TrueLabel9.Visible = FalseLabel10.Visible = FalseText1.SetFocusEnd SubPrivate Sub Form_Resize() 阻止用户任意改变窗体大小。If Me.WindowState = 0 Then 当窗体窗口运行时的课件状态为正常状态时才起作用，保证最大化的正常运行。