VB学习内容

1.'把编辑框中的内容全部选中并设光标
  text.SelStart = 0
  text.SelLength = Len(text.Text)       
  text.SetFocus
2.提示信息
 MsgBox "输入的参数错误", vbOKOnly, "错误"
3.定义一个可以返回字符串的函数
 Private Function spec(ByVal dsource1 As Double, ByVal dsource2 As Double) As String
      Dim sResult As String 
      spec = sResult
 End Function
4.读字符串的右边的N个字符
 UCase(Right(sTemp, n))
5.去除字符串两边的空格
T rim(sTemp)
6.把字符串转换为数值VAL()，把数值转化为字符串str()
7.判断文件是否存在
  '[函数]：文件是否存在
   '[参数]：被检查文件
   '[返回]：0，不存在；1，存在
 Public Function FileExist(FileDir As String) As Integer
    Dim sF As Long
    sF = GetFileAttributes(FileDir)
    FileExist = (sF <> -1)
    If sF = -1 Or sF = 0 Then
          FileExist = 0
    Else
          FileExist = 1
     ' MsgBox FileExist
    End If
  End Function   
8.打开文本文件并读内容
 Open App.Path & "\常用电阻阻值表.txt" For Input As #iFile '打开文件
        '逐行读取，并存入数组中
        Do While Not EOF(iFile)
                Line Input #iFile, sTemp
                arrTemp = Split(sTemp, ",") '分解读取的一行字符串，并存在字符数组中
                iArrTempLen = UBound(arrTemp) '计算数组的上限
                For i = 0 To iArrTempLen
                    '判断电阻值的单位来取值，如果最后的字符是K则不便，如果是M则乘1000，否则除1000
                    If UCase(Right(Trim(arrTemp(i)), 1)) = "K" Then
                        arrTable(iArrayLen) = Val(arrTemp(i))
                    ElseIf UCase(Right(Trim(arrTemp(i)), 1)) = "M" Then
                        arrTable(iArrayLen) = Val(arrTemp(i)) * 1000
                    Else
                        arrTable(iArrayLen) = Val(arrTemp(i)) / 1000
                    End If
                    'MsgBox (arrTable(iArrayLen))
                    iArrayLen = iArrayLen + 1
                   
                Next
        Loop
        'MsgBox iArrayLen
        Close #iFile
9.打开word文档
Option Explicit

Private Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" (ByVal hwnd As Long, _
    ByVal lpOperation As String, ByVal lpFile As String, ByVal lpParameters As String, _
    ByVal lpDirectory As String, ByVal nShowCmd As Long) As Long

Private Sub Command1_Click()
    ShellExecute Me.hwnd, "open", "c:a.doc", vbNullString, vbNullString, 3
End Sub

Private Sub Command2_Click()
    Dim WordApp As Word.Application
   
    Set WordApp = New Word.Application
    WordApp.Documents.Add ("c:a.doc")
    WordApp.Visible = True
 
    Set WordApp = Nothing
End Sub