Question

VB中如何判断窗体是否已加载

Answer 1

方法1：调用API函数FindWindow，通过窗体的Caption属性判断 Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" _ (ByVal lpClassName As String, ByVal lpWindowName As String) As Long Private Declare Function IsWindow Lib "user32" (ByVal hwnd As Long) As Long Dim lngAns As Long lngAns = FindWindow(vbNullString, "要查找窗体的CAPTION") lngAns = IsWindow(lngAns) If lngAns < 0 Then MsgBox "窗体已经被加载!", vbOKOnlyEndElseMsgBox "窗体未被加载!", vbOKOnlyEnd If方法2：访问Forms集合，也是通过Caption判断 '在Forms集合中进行遍历 For Each frmEach In Forms If frmEach Is frmTest Then '这样判断也可以 blnResult = TrueExit ForEnd If方法3：访问Forms集合，通过name判断 Private Function IsLoad(ByVal frmTest As Form) As Boolean Dim frmEach As Form Dim blnResult As Boolean blnResult = False '在Forms集合中进行遍历 For Each frmEach In Forms If frmEach.Name = frmTest.Name Then blnResult = TrueExit ForEnd IfNext

Answer 2

很简单,就只要定义一个全局变量
Dim A As Boolean
当窗体加载之后, 改变它的值
A = True
然后判断是否加载
If A=True Then
如果加载执行这里的代码