Public Class BookingForm Private bookedTimes As New Dictionary(Of String, Boolean) Private Sub BookingForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load ' 初始化bookedTimes字典 bookedTimes.Add("11:00-13:00", False) bookedTimes.Add("13:00-15:00", False) bookedTimes.Add("15:00-17:00", False) End Sub Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ListBox1.SelectedIndexChanged Dim selectedTime As String = ListBox1.SelectedItem.ToString() If bookedTimes(selectedTime) Then ' 时间段已经被预订，禁用提交按钮并显示提示 btnSubmit.Enabled = False MessageBox.Show(selectedTime & " has already been booked.") Else ' 时间段可以预订，启用提交按钮并将标志设置为已预订 btnSubmit.Enabled = True bookedTimes(selectedTime) = True End If End SubEnd Class给定关键词不在字典中怎么改？

时间: 2024-02-14 16:08:52 浏览: 161

在vb.net里怎么实现一个类似Windows10系统里自带的记事本程序的全部功能_(1).txt

为了实现这些目标，我们将逐一分析并提供VB.NET代码示例来创建类似Windows10系统自带的应用程序：记事本、画图、录音机、计算器以及图片查看器。 ### 1. 记事本 #### 功能需求： - 文件操作：打开、保存、另存为。 - 编辑操作：复制、粘贴、剪切、撤销、重做。 - 查找与替换。 - 字体样式调整。 #### VB.NET示例代码： ```vbnet Imports System.IO Imports System.Windows.Forms Public Class Notepad Private Sub NewDocumentToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles NewDocumentToolStripMenuItem.Click TextBox1.Clear() End Sub Private Sub OpenToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles OpenToolStripMenuItem.Click If OpenFileDialog1.ShowDialog() = DialogResult.OK Then TextBox1.Clear() TextBox1.LoadFile(OpenFileDialog1.FileName, RichTextBoxStreamType.PlainText) End If End Sub Private Sub SaveToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles SaveToolStripMenuItem.Click If SaveFileDialog1.ShowDialog() = DialogResult.OK Then TextBox1.SaveFile(SaveFileDialog1.FileName, RichTextBoxStreamType.PlainText) End If End Sub Private Sub ExitToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ExitToolStripMenuItem.Click Me.Close() End Sub Private Sub CutToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles CutToolStripMenuItem.Click TextBox1.Cut() End Sub Private Sub CopyToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles CopyToolStripMenuItem.Click TextBox1.Copy() End Sub Private Sub PasteToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles PasteToolStripMenuItem.Click TextBox1.Paste() End Sub Private Sub UndoToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles UndoToolStripMenuItem.Click TextBox1.Undo() End Sub Private Sub RedoToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles RedoToolStripMenuItem.Click TextBox1.Redo() End Sub Private Sub FindToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles FindToolStripMenuItem.Click ' 实现查找功能 End Sub Private Sub ReplaceToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ReplaceToolStripMenuItem.Click ' 实现替换功能 End Sub Private Sub FontToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles FontToolStripMenuItem.Click ' 实现字体选择功能 End Sub End Class ``` ### 2. 画图 #### 功能需求： - 绘制直线、矩形、圆形。 - 填充颜色。 - 橡皮擦工具。 - 颜色选择。 #### VB.NET示例代码： ```vbnet Public Class Paint Private isDrawing As Boolean = False Private startPoint As Point Private currentShape As String = "Line" Private Sub Paint_Load(sender As Object, e As EventArgs) Handles MyBase.Load Me.DoubleBuffered = True End Sub Private Sub PictureBox1_MouseDown(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseDown isDrawing = True startPoint = e.Location End Sub Private Sub PictureBox1_MouseUp(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseUp isDrawing = False DrawShape(startPoint, e.Location) End Sub Private Sub PictureBox1_MouseMove(sender As Object, e As MouseEventArgs) Handles PictureBox1.MouseMove If isDrawing Then DrawShape(startPoint, e.Location) End If End Sub Private Sub DrawShape(startPoint As Point, endPoint As Point) Dim g As Graphics = PictureBox1.CreateGraphics() Select Case currentShape Case "Line" g.DrawLine(Pens.Black, startPoint, endPoint) Case "Rectangle" g.DrawRectangle(Pens.Black, New Rectangle(startPoint, endPoint)) Case "Circle" g.DrawEllipse(Pens.Black, New Rectangle(startPoint, endPoint)) End Select End Sub Private Sub EraserToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles EraserToolStripMenuItem.Click ' 实现橡皮擦功能 End Sub Private Sub ColorToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ColorToolStripMenuItem.Click ' 实现颜色选择功能 End Sub End Class ``` ### 3. 录音机 #### 功能需求： - 开始录音。 - 停止录音。 - 播放录音。 - 导出录音文件。 #### VB.NET示例代码： ```vbnet Imports NAudio.Wave Imports System.IO Public Class Recorder Private recording As Boolean = False Private waveIn As WaveInEvent = Nothing Private waveFileWriter As WaveFileWriter = Nothing Private fileName As String = Path.Combine(Application.StartupPath, "recording.wav") Private Sub StartRecordingToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles StartRecordingToolStripMenuItem.Click waveIn = New WaveInEvent() waveIn.WaveFormat = New WaveFormat(44100, 1) waveIn.DataAvailable += AddressOf WaveInDataAvailable waveIn.StartRecording() waveFileWriter = New WaveFileWriter(fileName, waveIn.WaveFormat) recording = True End Sub Private Sub StopRecordingToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles StopRecordingToolStripMenuItem.Click waveIn.StopRecording() waveIn.Dispose() waveIn = Nothing waveFileWriter.Dispose() waveFileWriter = Nothing recording = False End Sub Private Sub PlayRecordingToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles PlayRecordingToolStripMenuItem.Click ' 实现播放功能 End Sub Private Sub WaveInDataAvailable(sender As Object, e As WaveInEventArgs) waveFileWriter.Write(e.Buffer, 0, e.BytesRecorded) End Sub End Class ``` ### 4. 计算器 #### 功能需求： - 四则运算。 - 二进制计算。 #### VB.NET示例代码： ```vbnet Public Class Calculator Private operation As String = "" Private result As Double = 0 Private Sub Button_Click(sender As Object, e As EventArgs) Handles Button0.Click, Button1.Click, Button2.Click, Button3.Click, Button4.Click, Button5.Click, Button6.Click, Button7.Click, Button8.Click, Button9.Click, ButtonAdd.Click, ButtonSubtract.Click, ButtonMultiply.Click, ButtonDivide.Click, ButtonEquals.Click, ButtonClear.Click, ButtonBackspace.Click Dim button As Button = CType(sender, Button) Select Case button.Name Case "Button0", "Button1", "Button2", "Button3", "Button4", "Button5", "Button6", "Button7", "Button8", "Button9" TextBox1.Text &= button.Text Case "ButtonAdd", "ButtonSubtract", "ButtonMultiply", "ButtonDivide" operation = button.Name.Substring(6) result = CDbl(TextBox1.Text) TextBox1.Clear() Case "ButtonEquals" TextBox1.Text = EvaluateExpression(result, TextBox1.Text, operation) result = 0 operation = "" Case "ButtonClear" TextBox1.Clear() result = 0 operation = "" Case "ButtonBackspace" TextBox1.Text = TextBox1.Text.Remove(TextBox1.Text.Length - 1) End Select End Sub Private Function EvaluateExpression(firstValue As Double, secondValue As String, operation As String) As String Dim value As Double = CDbl(secondValue) Select Case operation Case "Add" Return (firstValue + value).ToString() Case "Subtract" Return (firstValue - value).ToString() Case "Multiply" Return (firstValue * value).ToString() Case "Divide" Return (firstValue / value).ToString() End Select Return "" End Function End Class ``` ### 5. 图片查看器 #### 功能需求： - 打开图片文件。 - 显示图片。 - 放大缩小。 #### VB.NET示例代码： ```vbnet Imports System.Drawing Imports System.IO Imports System.Windows.Forms Public Class ImageViewer Private Sub OpenToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles OpenToolStripMenuItem.Click If OpenFileDialog1.ShowDialog() = DialogResult.OK Then PictureBox1.Image = Image.FromFile(OpenFileDialog1.FileName) End If End Sub Private Sub ZoomInToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ZoomInToolStripMenuItem.Click PictureBox1.SizeMode = PictureBoxSizeMode.Zoom End Sub Private Sub ZoomOutToolStripMenuItem_Click(sender As Object, e As EventArgs) Handles ZoomOutToolStripMenuItem.Click PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage End Sub End Class ``` 以上就是针对每个应用的基本功能实现的VB.NET代码示例。通过这些示例，你可以构建出类似Windows10系统自带的应用程序，并进一步扩展其功能。

你可以使用Dictionary类的ContainsKey方法来检查字典中是否存在指定的关键词。例如，如果你要检查"9:00-11:00"是否在字典中，可以这样做： ``` If Not bookedTimes.ContainsKey("9:00-11:00") Then ' 字典中不存在该关键词，进行相应处理 End If ``` 在这个例子中，你可以根据需要进行处理，例如向字典中添加该关键词，或者显示一个错误消息提示用户该时间段不可预订。

阅读全文

相关推荐

简单的VB鼠标拖动截图功能.rar_vb 截图_截屏

在vb.net里有一个AxWindowsMediaPlayer控件和一个按钮播放和一个多行内容的列表框.txt

编写vb.net代码，使得在窗体bookingform里面的listbox控件选择一个时间段（例如11:00-13:00）之后，该时间段不能被另一名用户再次选择

如何用Visual Basic 6.0精简版设计并实现一个基本的地鼠打洞游戏并给出代码

vb.net自动标注尺寸代码

VB.NET 检测布尔型变量的上升沿与下降沿，举例完善子程序并调用

VB中如何实现拖动放大缩小

vb.net 注册多个热键

怎么用vb.net实现Win+d的效果

Win+D的效果怎么用vb.net实现

用VB.NET写一个程序，模拟鼠标左击

vb.net最小化所有窗口的代码

最小化所有窗口的vb.net代码示例

VB.NET 怎么接收外部发来的字符串消息

Vb.net 窗体 在picturebox1里播放幻灯片指定目录图片

vb.net编写MODBUS tcp通讯

vb 当其他应用全屏时自动隐藏窗体

VB.NET 代码 窗体内任何控件修改过提醒

最新推荐

地级市GDP及产业结构数据-最新.zip

2006-2023年上市公司资产误定价Misp数据集（4.9万样本，含原始数据、代码及结果，最新）.zip

Altera和Xilinx FPGA的从串配置模式比较

Spring Boot 教程源码项目：含多种功能示例.zip

R语言高级建模课程全集-最新整理.zip

高清艺术文字图标资源，PNG和ICO格式免费下载

管理建模和仿真的文件

DMA技术：绕过CPU实现高效数据传输

SGM8701电压比较器如何在低功耗电池供电系统中实现高效率运作？

mui框架HTML5应用界面组件使用示例教程

Vb.net 窗体在picturebox1里播放幻灯片指定目录图片

VB.NET 代码窗体内任何控件修改过提醒