C#实现学员信息管理系统

//登陆入口页面
using system;
using system.collections.generic;
using system.componentmodel;
using system.data;
using system.data.sqlclient;
using system.drawing;
using system.linq;
using system.text;
using system.threading.tasks;
using system.windows.forms;

namespace 学员管理系统
{
 public partial class lo : form
 {
 public lo()
 {
  initializecomponent();
 }
  string sql= "data source=laptop-pcmbbb0n;initial catalog=db_student;trusted_connection=true;";
  private void log_load(object sender, eventargs e)
 {
  this.formborderstyle = formborderstyle.fixedtoolwindow;
  this.location = new point(screen.primaryscreen.bounds.width / 2 - this.width / 2, screen.primaryscreen.bounds.height / 2 - this.height / 2);
 }
 main main;
  private void button1_click(object sender, eventargs e)
 {
  try
  {
  string pwd =txtpwd.text;
  if (pwd.tostring() == "")
  {
   label2.visible = true;
   label2.text = "密码不能为空！";
  }
  else
  {
   if (pwd.equals((table.rows[0]["pwd"]).tostring()))
   {
   label2.visible = false;
   main = new main();
   main.show();
   this.visible = false;
   }
   else
   {
   label2.text = "密码不正确！";
   label2.visible = true;
   }
  }
  }
  catch (exception)
  {
  throw;
  }
 }
 datatable table = new datatable();
 private void txtid_leave(object sender, eventargs e)
 {
  try
  {
  int id = int.parse(txtid.text);
   //1.链接数据库对象
   sqlconnection sqlcon = new sqlconnection(sql);
  //3.创建数据库命令对象
  sqlcommand cmd = new sqlcommand();
  cmd.connection = sqlcon;
   cmd.commandtext = "select * from student where id=" + id;
   //5.数据适配器对象
  sqldataadapter sda = new sqldataadapter();
  sda.selectcommand = cmd;
  //6.这个table可以用来接受适配的最终结果
  sda.fill(table);
   if (table.rows.count > 0)
  {
   label1.visible = false;
  }
  else
  {
   label1.visible = true;
   label1.text = "输入id不存在！";
  }
  }
  catch (exception)
  {
  
  label1.visible = true;
  label1.text = "请输入纯数字id！";
  txtid.focus();
  txtid.text = "";
  }
 }
 private void button2_click_1(object sender, eventargs e)
 {
  register register = new register();
  register.showdialog();
  this.visible = true;
  label1.visible = false;
 }
 }
}

//注册页面
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 system.data.sqlclient;

namespace 学员管理系统
{
 public partial class register : form
 {
 public register()
 {
  initializecomponent();
 }
 string sql = "data source=laptop-pcmbbb0n;initial catalog=db_student;trusted_connection=true;";
  private void button1_click(object sender, eventargs e)
 {
  try
  {
  sqlconnection sqlcon = new sqlconnection(sql);
  string sqltxt = string.format("insert into student values('{0}','{1}','{2}','{3}','{4}')", textbox2.text, textbox1.text, textbox3.text, textbox4.text, textbox5.text);
  sqlcommand cmd = new sqlcommand(sqltxt, sqlcon);
  sqlcon.open();
  int res = cmd.executenonquery();
  if (res > 0)
  {
   messagebox.show("注册成功");
   textbox1.text = "";
   textbox2.text = "";
   textbox3.text = "";
   textbox4.text = "";
   textbox5.text = "";
   textbox1.focus();
  }
  }
  catch (exception)
  {
  throw;
  }
 }

//信息页面（可以进行数据库信息更改，删除，查看 以及翻页操作）
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 system.data.sqlclient;
namespace 学员管理系统
{
 public partial class main : form
 {
 public main()
 {
  initializecomponent();
 } 
  string strcon = "data source=laptop-pcmbbb0n;initial catalog=db_student;trusted_connection=true;";
 int countpage;
 int nowpage = 1;
 sqlconnection sqlcon;
  private void main_load(object sender, eventargs e)
 {
  sqlcon = new sqlconnection(strcon);
  //绑定页码信息
  try
  {
  string sql = "select count(*) from student";
  sqlcommand cmdl = new sqlcommand(sql, sqlcon);
  sqlcon.open();
  object res = cmdl.executescalar();
  if (res != null)
  {
   if ((int)res % 6 > 0)
   {
   countpage = ((int)res / 6) + 1;
   }
   else
   {
   countpage = (int)res / 6;
   }
  }
  }
  catch (exception)
  {
  throw;
  }
  finally
  {
  sqlcon.close();
  }
  //初始信息绑定
  try
  {
  setpage(sqlcon);
  datagridview1.autosizecolumnsmode = datagridviewautosizecolumnsmode.fill;
  datagridview1.rowheadersvisible = false;
  foreach (datagridviewcolumn dc in datagridview1.columns)
  {
   dc.sortmode = datagridviewcolumnsortmode.programmatic;
  }
  datagridview1.columnheadersdefaultcellstyle.alignment = datagridviewcontentalignment.middlecenter;
  datagridview1.defaultcellstyle.alignment = datagridviewcontentalignment.middlecenter;
  datagridview1.scrollbars = scrollbars.none;
  datagridview1.multiselect = false;
  datagridview1.selectionmode = datagridviewselectionmode.fullrowselect;
  datagridview1.allowusertoresizerows = false;
  datagridview1.allowusertoresizecolumns = false;   
  datagridview1.scrollbars = scrollbars.none;
  datagridview1.autosizecolumnsmode = datagridviewautosizecolumnsmode.fill;
  datagridview1.allowusertoaddrows = false;
  datagridview1.defaultcellstyle.alignment = datagridviewcontentalignment.middlecenter;
  datagridview1.columnheadersdefaultcellstyle.alignment = datagridviewcontentalignment.middlecenter;
  foreach (datagridviewcolumn item in datagridview1.columns)
  {
   item.sortmode = datagridviewcolumnsortmode.notsortable;
  }
  datagridview1.readonly = true;
  datagridview1.cellmousedown += datagridview1_cellmousedown;
  }
  catch (exception ex)
  {
  throw;
  }
  finally
  {
  sqlcon.close();
  }
 }
 private void setpage(sqlconnection sqlcon)
 {
  string sql = string.format("select id as '账号',name as '姓名',sex as '性别',age as '年龄',zhanli as '电话' from student where id in(select top(6) id from student where id not in (select top({0}) id from student order by id)order by id ) order by id", (nowpage - 1) * 6);
  sqlcommand cmd = new sqlcommand(sql, sqlcon);
  sqldataadapter sda = new sqldataadapter(cmd);
  dataset ds = new dataset();
  sda.fill(ds);
  datagridview1.datasource = ds.tables[0];
  label1.text = nowpage.tostring();
  label3.text = countpage.tostring();
 }
  private void datagridview1_cellmousedown(object sender, datagridviewcellmouseeventargs e)
 {
  if (e.button == mousebuttons.right && datagridview1.selectedrows.count > 0)
  {
  datagridview1.clearselection();
  datagridview1.rows[e.rowindex].selected = true;
  id.idd = (int)datagridview1.selectedcells[0].value;
  contextmenustrip1.show();
  }
 }
 private void 删除toolstripmenuitem1_click(object sender, eventargs e)
 {
  try
  {
  sqlconnection sqlcon = new sqlconnection(strcon);
  string sqltxt = "delete from student where id=" + id.idd;
  sqlcommand cmd = new sqlcommand(sqltxt, sqlcon);
  sqlcon.open();
  int res = cmd.executenonquery();
  if (res > 0)
  {
   messagebox.show("删除成功！");
   main ma = new 学员管理系统.main();
   ma.show();
   this.visible = false;
  }
  }
  catch (exception)
  {
  throw;
  }
 }
 private void 修改密码toolstripmenuitem_click(object sender, eventargs e)
 {
  xiugai xiu = new xiugai();
  xiu.showdialog();
  this.visible = false;
 }
 private void 查看详细信息toolstripmenuitem_click(object sender, eventargs e)
 {
  chakan cha = new chakan();
  cha.showdialog();
  this.visible = false;
 }
 private void 下一页toolstripmenuitem_click(object sender, eventargs e)
 {
  
  if (nowpage >= countpage)
  {
  return;
  }
  else
  {
  nowpage++;
  setpage(sqlcon);
  }
 }
  private void 上一页toolstripmenuitem_click(object sender, eventargs e)
 {
  if (nowpage <= 1)
  {
  return;
  }
  else
  {
  nowpage--;
  setpage(sqlcon);
  }
 }
 }
}

/查看详细信息
using system;
using system.collections.generic;
using system.componentmodel;
using system.data;
using system.data.sqlclient;
using system.drawing;
using system.linq;
using system.text;
using system.threading.tasks;
using system.windows.forms;

namespace 学员管理系统
{
 public partial class chakan : form
 {
 public chakan()
 {
  initializecomponent();
 }
  private void button1_click(object sender, eventargs e)
 {
  main ma = new 学员管理系统.main();
  ma.show();
  this.visible = false; 
 }
 string sql = "data source=laptop-pcmbbb0n;initial catalog=db_student;trusted_connection=true;";
 private void chakan_load(object sender, eventargs e)
 {
  try
  {
  sqlconnection sqlcon = new sqlconnection(sql);
  string sqltxt = "select * from student where id="+id.idd; 
  sqlcommand cmd = new sqlcommand(sqltxt, sqlcon);
  sqlcon.open();
  sqldataadapter sda = new sqldataadapter(cmd);
  datatable table = new datatable();
  sda.fill(table);
  name1.text = (table.rows[0]["name"]).tostring();
  id1.text = (table.rows[0]["id"]).tostring();
  pwd.text = (table.rows[0]["pwd"]).tostring();
  sex.text = (table.rows[0]["sex"]).tostring();
  age.text = (table.rows[0]["age"]).tostring();
  zhanli.text = (table.rows[0]["zhanli"]).tostring();
  }
  catch (exception)
  {
  throw;
  }
 }
 }
}

//创建一个类用来存储用户账号
using system;
using system.collections.generic;
using system.linq;
using system.text;
using system.threading.tasks;
namespace 学员管理系统
{
 public class id
 {
 public static int idd;
 public static int idd
 {
  get
  {
  return idd;
  }
  set
  {
  idd = value;
  }
 }
 }
}

//修改密码
using system.data;
using system.drawing;
using system.linq;
using system.text;
using system.threading.tasks;
using system.windows.forms;
using system.data.sqlclient;

namespace 学员管理系统
{
 public partial class xiugai : form
 {
 public xiugai()
 {
  initializecomponent();
 }
 string sql = "data source=laptop-pcmbbb0n;initial catalog=db_student;trusted_connection=true;";
 private void button1_click(object sender, eventargs e)
 {
  string yuan = textbox1.text;
  string new = textbox2.text;
  string new2 = textbox3.text;
  if (yuan=="")
  {
  label4.visible = true;
  textbox1.focus();
  }
  else
  {
  if (new=="")
  {
   label5.visible = true;
   textbox2.focus();
  }
  else
  {
   if (new2==""||new2!=new)
   {
   label6.visible = true;
   textbox3.focus();
   }
   else
   {
   try
   {
    int num = int.parse(yuan);
    sqlconnection sqlcon = new sqlconnection(sql);
    string sqltext = "update student set pwd=" + new2 + "where id="+id.idd;
    //string sqltext = "update studentinfor set pwd=" + new2 + "where id="+id.idd;
    sqlcommand cmd = new sqlcommand(sqltext,sqlcon);
    sqlcon.open();
    int res = cmd.executenonquery();
    if (res>0)
    {
    messagebox.show("修改成功");
    }
   }
   catch (exception)
   {
    throw;
   }
   }
  }
  }
 }
 }
}