请注意，程式码是在binarySearchBox的文字方块中执行二进制搜寻，而不是ListBox1文字方块中的值。
需要将添加到ListBox1的值转换为Array数组以进行存储的代码。string[]myArray = listBox1.Items.Cast<string>().ToArray();，然后搜索ListBox1。
代码显示如下：

private void BinarySearch_Click(object sender, EventArgs e)
    {
        string[]myArray = listBox1.Items.Cast<string>().ToArray();
        Array.Sort(myArray, 0, emptyPtr);     
        SearchArray(myArray, binarySearchBox.Text);

    }
    private void SearchArray(Array array, object value)
    {
        string[] myArray = listBox1.Items.Cast<string>().ToArray();
        Array.Sort(myArray, 0, emptyPtr);
        string target = binarySearchBox.Text;
        int numIndex = Array.BinarySearch(array, target);

        if (numIndex < 0)
        {
            displayBox2.Text = "The element to search for " + target + " is not found.";
        }
        else if (numIndex >= 0)
        {
            displayBox2.Text = "The element to search for " + target + " is at index: " + numIndex;
        }
    }

    private void linearSearch_Click(object sender, EventArgs e)
    {
        string[] myArray = listBox1.Items.Cast<string>().ToArray();
        string target = linearSearchBox.Text;
        bool found = false;

        for (int x = 0; x < myArray.Length; x++)
        {
            if (myArray[x] == target)
            {
                displayBox2.Text = target + " Found at index " + (x + 1) +
                             "\r\n";
                linearSearchBox.Clear();
                linearSearchBox.Focus();
                return;
            }
        }
        if (!found)
        {
            displayBox2.Text = "Not Found, try again." + "\r\n";
            linearSearchBox.Clear();
            linearSearchBox.Focus();
        }
    }