Vb.net 根据字符串位置复制RichTextBox字符串

我有一个长的TXT字符串导入到RichTextBox中。我试图使用基于文本字符串的起点和终点复制该文本的一部分。这是我到目前为止得到的

    Dim StartsearchString As String = "MyStartString"
    Dim EndSearchString As String = "MyEndString"
    Dim Length As Integer
    Dim StartPoint As Integer
    Dim EndPoint As Integer
    Length1 = Len(StartsearchString)
    Length2 = Len(EndSearchString)
    StartPoint = Form2.RichTextBox2.Find(StartsearchString) + Length1
    EndPoint = Form2.RichTextBox2.Find(EndSearchString) - Length2

如何在起点和终点之间复制文本并将其粘贴到新的RichTextBox中

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谢谢。

您的端点已关闭，因为您不必减去结束字符串的长度。也就是说，Find方法正在查找该索引的开头

我使用SubString函数以这种方式重新处理它：

Dim StartsearchString As String = "MyStartString"
Dim EndSearchString As String = "MyEndString"
Dim StartPoint As Integer = RichTextBox2.Find(StartsearchString)
Dim EndPoint As Integer = RichTextBox2.Find(EndSearchString)
If EndPoint > StartPoint Then
  OtherRTB.Text = RichTextBox2.Text.Substring(
                     StartPoint + StartsearchString.Length,
                     EndPoint - StartPoint - StartsearchString.Length)
End If