代码如下：
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Windows.Forms;
using System.Xml.Linq;
namespace XMLAction
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
/// <summary>
/// 从xml加载用户
/// </summary>
/// <param name="dgv">DataGridView</param>
private void LoadUserData(DataGridView dgv)
{
//加载xml文件
XDocument xDoc = XDocument.Load("UserData.xml");
//获取根节点
XElement root = xDoc.Root;
List<User> list = new List<User>();
//循环加载用户
foreach (XElement item in root.Elements("user"))
{
User model = new User(item.Attribute("id").Value.ToString(),
item.Element("name").Value.ToString(),
item.Element("pwd").Value.ToString());
list.Add(model);
}
dgv.DataSource = list;
}
private void Form1_Load(object sender, EventArgs e)
{
if (!System.IO.File.Exists(Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location),"UserData.xml")))//Directory.GetCurrentDirectory(), "UserData.xml")))
{
//MessageBox.Show("程序第一次运行,请先使用[CreateXML.exe]程序完成环境配置");
//Application.Exit();
//创建xml对象
XDocument xDoc = new XDocument();
//创建根节点
XElement root = new XElement("Users");
//添加根节点
xDoc.Add(root);
//保存xml文件
xDoc.Save("UserData.xml");
}
dataGridView1.MultiSelect = false;//取消多行
dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;//选中整行
txtUId.ReadOnly = true;//修改时Id是不可变的
LoadUserData(dataGridView1);
}
private void btnRegister_Click(object sender, EventArgs e)
{
string id = txtRId.Text.Trim();
string name = txtRName.Text.Trim();
string pwd = txtRPwd.Text;
if (string.IsNullOrEmpty(id) || string.IsNullOrEmpty(name) || string.IsNullOrEmpty(pwd))
{
MessageBox.Show("请填写注册信息");
return;
}
//加载xml
XDocument xDoc = XDocument.Load("UserData.xml");
//获取根节点
XElement root = xDoc.Root;
//搜索当前注册用户ID是否存在
XElement isHaveUser = root.Elements("user").SingleOrDefault(p => p.Attribute("id").Value.ToString() == id);
if (isHaveUser == null)
{
//创建user节点对象
XElement userElement = new XElement("user");
userElement.SetAttributeValue("id", id);
//增加两个子节点
userElement.SetElementValue("name", name);
userElement.SetElementValue("pwd", pwd);
//保存user节点
root.Add(userElement);
xDoc.Save("UserData.xml");
MessageBox.Show("成功!注册用户ID为【" + id + "】");
LoadUserData(dataGridView1);
}
else
{
MessageBox.Show("用户ID【" + id + "】已存在");
}
}
//双击DataGridView控件就刷新一次数据
private void dataGridView1_DoubleClick(object sender, EventArgs e)
{
LoadUserData(dataGridView1);
}
private void btnDelete_Click(object sender, EventArgs e)
{
if (MessageBox.Show("确认删除?", "操作提示", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == System.Windows.Forms.DialogResult.Yes)
{
string id = dataGridView1.SelectedRows[0].Cells[0].Value.ToString();
//加载xml
XDocument xDoc = XDocument.Load("UserData.xml");
//获取根节点
XElement root = xDoc.Root;
try
{
//获取这个节点
XElement userElement = root.Elements("user").Where(p => p.Attribute("id").Value.ToString() == id).Single();
//删除这个节点
userElement.Remove();
//保存操作后的xml文件
xDoc.Save("UserData.xml");
MessageBox.Show("删除成功");
//加载数据
LoadUserData(dataGridView1);
}
catch(Exception ex)
{
MessageBox.Show("删除失败,请刷新后重试:"+ex.Message);
}
}
else
MessageBox.Show("未删除");
}
//DataGridView行焦点改变
private void dataGridView1_RowEnter(object sender, DataGridViewCellEventArgs e)
{
string id = dataGridView1.Rows[e.RowIndex].Cells[0].Value.ToString();
string name = dataGridView1.Rows[e.RowIndex].Cells[1].Value.ToString();
string pwd = dataGridView1.Rows[e.RowIndex].Cells[2].Value.ToString();
txtUId.Text = id;
txtUName.Text = name;
txtUPwd.Text = pwd;
}
private void btnUpdate_Click(object sender, EventArgs e)
{
string id = txtUId.Text.Trim();
string name = txtUName.Text.Trim();
string pwd = txtUPwd.Text;
//加载xml文件
XDocument xDoc = XDocument.Load("UserData.xml");
//获取根节点
XElement root = xDoc.Root;
//找到要修改的用户
try
{
XElement crrentElement = root.Elements("user").Where(p => p.Attribute("id").Value.ToString() == id).Single();
crrentElement.SetElementValue("name", name);
crrentElement.SetElementValue("pwd", pwd);
//完成修改操作后，保存xml文件
xDoc.Save("UserData.xml");
MessageBox.Show("修改成功");
LoadUserData(dataGridView1);
}
catch
{
MessageBox.Show("修改失败,请刷新后重试");
}
}
private void btnLogin_Click(object sender, EventArgs e)
{
string id = txtLId.Text.Trim();
string pwd = txtLPwd.Text;
if (string.IsNullOrEmpty(id) || string.IsNullOrEmpty(pwd))
{
MessageBox.Show("请填写用户Id和密码");
return;
}
//加载xml文件
XDocument xDoc = XDocument.Load("UserData.xml");
//获取根节点
XElement root = xDoc.Root;
try
{
XElement user = root.Elements("user").Where(p => p.Attribute("id").Value.ToString() == id).Single();
if (user.Element("pwd").Value.ToString() == pwd)
MessageBox.Show("登录成功");
else
MessageBox.Show("密码错误");
}
catch
{
MessageBox.Show("用户不存在");
}
}
}
public class User
{
public User(string id, string name, string pwd)
{
this.Id = id;
this.Name = name;
this.Pwd = pwd;
}
public string Id { get; set; }
public string Name { get; set; }
public string Pwd { get; set; }
}
}