c# - 将文本框中的 url 添加到 Windows 窗体应用程序 c# 中的列表框

Question

我是编程新手。在 windows 窗体应用程序中，我希望用户可以在文本框中编写一个 url 并在列表框中添加（带按钮）作为收藏列表，然后用户可以单击列表框然后转到浏览器，最后可以保存并打开列表？没有 Microsoft Sql 数据库。我需要源代码。

文本框：（输入您的网站）：www.google.com

按钮：添加到列表框

列表框：WWW.Google.com

按钮：保存

按钮：打开

Answer 1

You have to save the ListBox.Items as plain text file if not wanting to use database. Without binding, this simple problem becomes a little nasty if you start digging into writing it. Here is one of the solution you may need:

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }
    int lastIndex = -1;
    bool suppressSelectedIndexChanged;
    //Click event handler for buttonAdd
    private void buttonAdd_Click(object sender, EventArgs e)
    {
        listBox1.Items.Add(textBox1.Text);
        suppressSelectedIndexChanged = true;
        listBox1.SelectedIndex = listBox1.Items.Count - 1;
        suppressSelectedIndexChanged = false;
    }
    //Click event handler for buttonRemove
    private void buttonRemove_Click(object sender, EventArgs e)
    {
        if (listBox1.SelectedIndices.Count == 0) return;
        int k = listBox1.SelectedIndices[0];
        suppressSelectedIndexChanged = true;
        for (int i = listBox1.SelectedIndices.Count - 1; i >= 0; i--)
            listBox1.Items.RemoveAt(listBox1.SelectedIndices[i]);
        suppressSelectedIndexChanged = false;
        lastIndex = -1;
        listBox1.SelectedIndex = k < listBox1.Items.Count ? k : listBox1.Items.Count - 1;
        if (listBox1.Items.Count == 0) textBox1.Clear();
    }
    //Click event handler for buttonSave
    private void buttonSave_Click(object sender, EventArgs e)
    {            
        SaveFileDialog save = new SaveFileDialog();
        save.Filter = "URLs file|*.urls";
        save.FileOk += (s, ev) =>
        {
            using (StreamWriter writer = File.CreateText(save.FileName))
            {
                foreach (object item in listBox1.Items)
                {
                    writer.WriteLine(item.ToString());
                }
            }
        };
        save.ShowDialog();
    }
    //Click event handler for buttonOpen
    private void buttonOpen_Click(object sender, EventArgs e)
    {
        OpenFileDialog open = new OpenFileDialog();
        open.Filter = "URLs file|*.urls";
        open.FileOk += (s, ev) =>
        {
            listBox1.Items.Clear();
            using (StreamReader reader = File.OpenText(open.FileName))
            {
                string line = "";
                while ((line = reader.ReadLine()) != null)
                {
                    listBox1.Items.Add(line);
                }
            }
        };
        open.ShowDialog();
    }
    //SelectedIndexChanged event handler for listBox1
    private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (suppressSelectedIndexChanged) return;
        if (lastIndex > -1)
        {
            listBox1.Items[lastIndex] = textBox1.Text;                
        }            
        lastIndex = listBox1.SelectedIndex;
        if (listBox1.SelectedIndex > -1)
            textBox1.Text = listBox1.Items[listBox1.SelectedIndex].ToString();
    }
    //Click event handler for buttonVisit
    private void buttonVisit_Click(object sender, EventArgs e)
    {
        if (listBox1.SelectedItem == null) return;
        System.Diagnostics.Process.Start(listBox1.SelectedItem.ToString());
    }
}

Here is the GUI screen shot for you to know which controls are needed:

Answer 2

     private void btnAdd_Click(object sender, EventArgs e)
    {
        string _webstring = @"http://";
        string _website = _webstring + textBox1.Text;
        listBox1.Items.Add(_website);

        using (StreamWriter w = File.AppendText("websites.txt"))
        {
                WriteLog(_website, w);

        }
        using (StreamReader r = File.OpenText("websites.txt"))
        {
            DisposeLog(r);
        }
    }

    private void btnLaunch_Click(object sender, EventArgs e)
    {
        System.Diagnostics.Process.Start("iexplore.exe", listBox1.SelectedItem.ToString());
    }

    private void btnSave_Click(object sender, EventArgs e)
    {
        using (StreamWriter w = File.AppendText("websites.txt"))
        {
            foreach (string items in listBox1.Items)
            {
                WriteLog(items, w);
            }
        }
        using (StreamReader r = File.OpenText("websites.txt"))
        {
            DisposeLog(r);
        }
    }


    public static void WriteLog(string logMessage, TextWriter w)
    {
        w.WriteLine(logMessage, logMessage);
    }

    public static void DisposeLog(StreamReader r)
    {
        string line;
        while ((line = r.ReadLine()) != null)
        {
            Console.WriteLine(line);
        }
    }

    private void btnRetrieve_Click(object sender, EventArgs e)
    {
        using (TextReader txtRead = File.OpenText("Websites.txt"))
        {
            string _text = "";
            string[] _textArray = null;
            while ((_text = txtRead.ReadLine()) != null)
            {
                _textArray = _text.Split('\t');
                listBox1.Items.Add(txtRead.ReadLine());
            }
            txtRead.Close();
        }
    }

希望这有帮助..谢谢