如何在不替换第一个输入的情况下在文本框中添加新显示

Question

您好，我正在创建一个类似聊天的应用程序。你能帮帮我吗？ 当我输入新消息时，初始显示的消息被替换:(

请看下面我的代码：

Private Sub saveMessage()    

    FileName = Format(Now, "MMddyyyyhhmmss")
    Dim RecipientFile As String

    If CurrentRecipient = "Edward" Then
        RecipientFile = RecipientFolder & FileName & ".txt"
    ElseIf CurrentRecipient = "Criziel" Then
        RecipientFile = RecipientFolder & FileName & ".txt"
    ElseIf CurrentRecipient = "Jerome" Then
        RecipientFile = RecipientFile & FileName & ".txt"
    Else
        Exit Sub
    End If

    Dim Writer As IO.StreamWriter
    Writer = New IO.StreamWriter(RecipientFile)
    Writer.Write(MainRichTextBox.Text)

    Writer.Close()

    ShowtextRichTextBox.Text = (User & " : ") & MainRichTextBox.Text
    MainRichTextBox.Clear()
End Sub

提前致谢！ :*

Answer 1

您的以下代码只是将最新值分配（替换）到富文本框，

ShowtextRichTextBox.Text = (User & " : ") & MainRichTextBox.Text

相反，您应该附加如下文本，

ShowtextRichTextBox.Text &= (User & " : ") & MainRichTextBox.Text

此外，您可以尝试使用 RichTextBox 的内置方法来附加文本，例如 ShowtextRichTextBox.AppendText((User & " : ") & MainRichTextBox.Text)

注意：追加时，还应在新文本前添加换行符，如ShowtextRichTextBox.Text &= Environment.NewLine & (User & " : ") & MainRichTextBox.Text.

修改后的代码，

Private Sub saveMessage()

    FileName = Format(Now, "MMddyyyyhhmmss")
    Dim RecipientFile As String

    If CurrentRecipient = "Edward" Then
        RecipientFile = RecipientFolder & FileName & ".txt"
    ElseIf CurrentRecipient = "Criziel" Then
        RecipientFile = RecipientFolder & FileName & ".txt"
    ElseIf CurrentRecipient = "Jerome" Then
        RecipientFile = RecipientFile & FileName & ".txt"
    Else
        Exit Sub
    End If

    Dim Writer As IO.StreamWriter
    Writer = New IO.StreamWriter(RecipientFile)
    Writer.Write(MainRichTextBox.Text)

    Writer.Close()

    ShowtextRichTextBox.Text &= Environment.NewLine & (User & " : ") & MainRichTextBox.Text
    MainRichTextBox.Clear()
End Sub