FilterInfoCollection videoDevices;//摄像头设备集合 VideoCaptureDevice videoSource;//捕获设备源 const int delaytime = 500; //扫码间隔时间 ms int totalTime; //扫码最长时间 public Form1() { InitializeComponent(); } private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { } private void button1_Click(object sender, EventArgs e) { comboBox1.Items.Clear(); videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice); for (int i = 0; i < videoDevices.Count; i++) comboBox1.Items.Add(videoDevices[i].Name); comboBox1.Text = comboBox1.Items[0].ToString(); } private void button2_Click(object sender, EventArgs e) { if (comboBox1.Text == null) return; videoSource = new VideoCaptureDevice(videoDevices[comboBox1.SelectedIndex].MonikerString); videoSourcePlayer1.VideoSource = videoSource; videoSourcePlayer1.Start(); textBox1.Text = "开始识读"; timer1.Interval = delaytime; timer1.Start(); totalTime = 0; } private void timer1_Tick(object sender, EventArgs e) { if (totalTime >= 20000)// 最多读20秒 { timer1.Stop(); textBox1.Text = "未识别到条形码"; return; } Bitmap barcodeImage; barcodeImage = videoSourcePlayer1.GetCurrentVideoFrame();//拍摄 if (barcodeImage != null) { // 识读条形码 BarcodeReader reader = new BarcodeReader(); reader.Options.CharacterSet = "UTF-8"; reader.Options.PossibleFormats = new List<BarcodeFormat>() { BarcodeFormat.CODE_128 }; Result resultBarcode = reader.Decode(barcodeImage); if (resultBarcode != null) { textBox1.Text = ""; textBox1.AppendText(resultBarcode.Text); timer1.Stop(); return; } } totalTime += delaytime; textBox1.Text = totalTime.ToString() + " ms"; //if (totalTime == 3000) // picture.Save("测试图片.bmp"); }怎么设置锁定后置摄像头 不打开前置摄像头

在上述代码中，可以通过修改以下代码来锁定使用后置摄像头：

videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice);
for (int i = 0; i < videoDevices.Count; i++)
{
    if (videoDevices[i].Name.ToLower().Contains("back"))
    {
        comboBox1.Items.Add(videoDevices[i].Name);
    }
}
comboBox1.Text = comboBox1.Items[0].ToString();

在上述代码中，我们使用了FilterInfoCollection类的构造函数来获取所有可用的摄像头设备。然后，我们使用一个for循环来遍历所有的设备，并检查其名称是否包含“back”字样，如果包含，则将其添加到下拉框中。最后，我们将下拉框的文本设置为第一个摄像头设备的名称。

这样，在打开摄像头时，就会默认使用第一个名称中包含“back”的摄像头设备，从而实现了锁定后置摄像头的功能。

相关问题

FilterInfoCollection videoDevices;//摄像头设备集合 VideoCaptureDevice videoSource;//捕获设备源 const int delaytime = 500; //扫码间隔时间 ms int totalTime; //扫码最长时间 public Form1() { InitializeComponent(); } private void comboBox1_SelectedIndexChanged(object sender, EventArgs e) { } private void button1_Click(object sender, EventArgs e) { comboBox1.Items.Clear(); videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice); for (int i = 0; i < videoDevices.Count; i++) comboBox1.Items.Add(videoDevices[i].Name); comboBox1.Text = comboBox1.Items[0].ToString(); } private void button2_Click(object sender, EventArgs e) { if (comboBox1.Text == null) return; videoSource = new VideoCaptureDevice(videoDevices[comboBox1.SelectedIndex].MonikerString); videoSourcePlayer1.VideoSource = videoSource; videoSourcePlayer1.Start(); textBox1.Text = "开始识读"; timer1.Interval = delaytime; timer1.Start(); totalTime = 0; } private void timer1_Tick(object sender, EventArgs e) { if (totalTime >= 20000)// 最多读20秒 { timer1.Stop(); textBox1.Text = "未识别到条形码"; return; } Bitmap barcodeImage; barcodeImage = videoSourcePlayer1.GetCurrentVideoFrame();//拍摄 if (barcodeImage != null) { // 识读条形码 BarcodeReader reader = new BarcodeReader(); reader.Options.CharacterSet = "UTF-8"; reader.Options.PossibleFormats = new List<BarcodeFormat>() { BarcodeFormat.CODE_128 }; Result resultBarcode = reader.Decode(barcodeImage); if (resultBarcode != null) { textBox1.Text = ""; textBox1.AppendText(resultBarcode.Text); timer1.Stop(); return; } } totalTime += delaytime; textBox1.Text = totalTime.ToString() + " ms"; //if (totalTime == 3000) // picture.Save("测试图片.bmp");怎么设置锁定后置摄像头不打开前置摄像头

要想实现锁定后置摄像头，不打开前置摄像头，可以在获取摄像头设备源时，指定后置摄像头的设备。具体实现方法如下：

1. 获取所有视频设备的集合

videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice);

2. 遍历视频设备集合，找到后置摄像头对应的设备

foreach (FilterInfo device in videoDevices)
{
    if (device.Name == "后置摄像头名称")
    {
        videoSource = new VideoCaptureDevice(device.MonikerString);
        break;
    }
}

3. 如果找到后置摄像头对应的设备，则使用该设备进行视频捕捉，否则提示用户没有找到后置摄像头

if (videoSource != null)
{
    videoSourcePlayer1.VideoSource = videoSource;
    videoSourcePlayer1.Start();
}
else
{
    MessageBox.Show("没有找到后置摄像头！");
}

需要注意的是，不同手机的后置摄像头名称可能不同，需要根据具体手机进行调试和修改。同时，如果找不到后置摄像头对应的设备，则需要在代码中处理异常情况。

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; using AForge; using AForge.Controls; using AForge.Neuro; using AForge.Video; using AForge.Video.DirectShow; using static recharge.Form1; namespace recharge { public partial class Form1 : Form { FilterInfoCollection videoDevices;//摄像头设备集合 VideoCaptureDevice videoSource;//捕获设备源 public int selctedDeviceIndxe = 0; Bitmap img;//处理图片 public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { //先检测电脑所有的摄像头 videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice); MessageBox.Show("检测到了" + videoDevices.ToString() + "个摄像头！"); } // CS0021.cs // compile with: /reference:CPP0021.dll private void pictureBox1_Click(object sender, EventArgs e) { } private void videoSourcePlayer1_Click(object sender, EventArgs e) { } private void button1_Click(object sender, EventArgs e) { videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice); selctedDeviceIndxe = 0; videoSource = new VideoCaptureDevice(videoDevices[selctedDeviceIndxe].MonikerString); videoSource.VideoResolution = videoSource.VideoCapabilities[selctedDeviceIndxe]; videoSourcePlayer1.VideoSource = videoSource; videoSourcePlayer1.Start(); img = videoSourcePlayer1.GetCurrentVideoFrame(); } } }

根据您提供的代码，问题出现在 `videoSource = new VideoCaptureDevice(videoDevices[selctedDeviceIndxe].MonikerString);` 这一行，因为 `videoDevices` 是一个 `FilterInfoCollection` 类型的对象，而这个类型不支持通过方括号进行索引操作。

要解决这个问题，您可以使用 `videoDevices[selctedDeviceIndxe]` 的返回值来获取当前选中的 `FilterInfo` 对象，然后再使用它的 `MonikerString` 属性来创建 `VideoCaptureDevice` 对象。修改后的代码如下：

FilterInfo selectedDevice = videoDevices[selctedDeviceIndxe];
videoSource = new VideoCaptureDevice(selectedDevice.MonikerString);
videoSource.VideoResolution = videoSource.VideoCapabilities[selectedDevice];

这样就可以避免使用带有方括号的索引操作了。希望这可以帮助到您！