计算sinx.frm

Visual Basic课程举例1 有很好的例题

VERSION 5.00
Begin VB.Form Form1 
   Caption         =   "Calc Sin(x)"
   ClientHeight    =   2640
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   6390
   BeginProperty Font 
      Name            =   "Arial Black"
      Size            =   15.75
      Charset         =   0
      Weight          =   400
      Underline       =   0   'False
      Italic          =   0   'False
      Strikethrough   =   0   'False
   EndProperty
   LinkTopic       =   "Form1"
   ScaleHeight     =   2640
   ScaleWidth      =   6390
   StartUpPosition =   3  '窗口缺省
   Begin VB.CommandButton Command1 
      Caption         =   "Sinx="
      Height          =   495
      Left            =   120
      TabIndex        =   2
      Top             =   1200
      Width           =   1335
   End
   Begin VB.TextBox Text1 
      Height          =   525
      Left            =   1560
      TabIndex        =   0
      Top             =   360
      Width           =   4335
   End
   Begin VB.Label Label4 
      Caption         =   "结果对比"
      Height          =   495
      Left            =   120
      TabIndex        =   5
      Top             =   1920
      Width           =   1335
   End
   Begin VB.Label Label3 
      BackColor       =   &H00FFFFC0&
      Height          =   495
      Left            =   1560
      TabIndex        =   4
      Top             =   1920
      Width           =   4335
   End
   Begin VB.Label Label2 
      BackColor       =   &H80000009&
      Height          =   495
      Left            =   1560
      TabIndex        =   3
      Top             =   1200
      Width           =   4335
   End
   Begin VB.Label Label1 
      Caption         =   "X="
      Height          =   615
      Left            =   840
      TabIndex        =   1
      Top             =   360
      Width           =   615
   End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
DefDbl A-Z
Private Sub Command1_Click()
 Dim X, Sum, T, I%
 
 X = Val(Text1)
 
 T = X
 I = 1
 Do
    Sum = Sum + T
    T = -T * X * X / (2 * I) / (2 * I + 1)
    I = I + 1
 Loop While Abs(T) > 0.000000000000001
 
 Label2.Caption = Format(Sum, "0.##################")
 Label3.Caption = Format(Sin(X), "0.##################")
End Sub