SendMessage如何获取text1中的内容，详细一点

看看 下面的好用吗？给你个复杂的，我还有个简单的，感兴趣的话再给你。
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hWnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Declare Sub RtlMoveMemory Lib "KERNEL32" (lpvDest As Any, lpvSource As Any, ByVal cbCopy As Long)
Private Const EM_GETLINECOUNT = &HBA
Private Const EM_GETLINE = &HC4
Private Const EM_LINEFROMCHAR = &HC9
Private Const EM_LINELENGTH = &HC1
Private Const EM_LINEINDEX = &HBB

Sub TB_GetLine(IsText As TextBox, ByVal whichLine As Long, Line As String)

Dim length As Long, bArr() As Byte, bArr2() As Byte, lc As Long

lc = SendMessage(IsText.hWnd, EM_LINEINDEX, whichLine,