kmpdfkit_demo/ComPDFKit.Demo/PasswordDlg.cs

using System.Windows.Forms;

namespace ComPDFKitDemo
{
    public partial class PasswordDlg : Form
    {
        public string password = "";
        public int press_key = 0;
        public PasswordDlg()
        {
            InitializeComponent();
        }

        private void passwordTextBox_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar == 13)
            {
                press_key = 13;
                password = this.passwordTextBox.Text;
                this.Close();
            }
        }
    }
}