Jsp&Servlet入门级项目全程实录第8讲

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1、添加dao
  public int studentAdd(Connection con,Student student)throws Exception{
          String sql="insert into t_student values(null,?,?,?,?,?,?,?)";
          PreparedStatement pstmt=con.prepareStatement(sql);
          pstmt.setString(1, student.getStuNo());
          pstmt.setString(2, student.getStuName());
          pstmt.setString(3, student.getSex());
          pstmt.setString(4, DateUtil.formatDate(student.getBirthday(), "yyyy-MM-dd"));
          pstmt.setInt(5, student.getGradeId());
          pstmt.setString(6, student.getEmail());
          pstmt.setString(7, student.getStuDesc());
          return pstmt.executeUpdate();
     }

2、修改dao
public int studentModify(Connection con,Student student)throws Exception{
          String sql="update t_student set stuNo=?,stuName=?,sex=?,birthday=?,gradeId=?,email=?,stuDesc=? where stuId=?";
          PreparedStatement pstmt=con.prepareStatement(sql);
          pstmt.setString(1, student.getStuNo());
          pstmt.setString(2, student.getStuName());
          pstmt.setString(3, student.getSex());
          pstmt.setString(4, DateUtil.formatDate(student.getBirthday(), "yyyy-MM-dd"));
          pstmt.setInt(5, student.getGradeId());
          pstmt.setString(6, student.getEmail());
          pstmt.setString(7, student.getStuDesc());
          pstmt.setInt(8, student.getStuId());
          return pstmt.executeUpdate();
     }

3、修改servlet
     request.setCharacterEncoding("utf-8");
          String stuNo=request.getParameter("stuNo");
          String stuName=request.getParameter("stuName");
          String sex=request.getParameter("sex");
          String birthday=request.getParameter("birthday");
          String gradeId=request.getParameter("gradeId");
          String email=request.getParameter("email");
          String stuDesc=request.getParameter("stuDesc");
          String stuId=request.getParameter("stuId");

          Student student=null;
          try {
               student=new Student( stuNo, stuName, sex, DateUtil.formatString(birthday, "yyyy-MM-dd"),
                    Integer.parseInt(gradeId), email, stuDesc);
          } catch (Exception e) {
               e.printStackTrace();
          }

          if(StringUtil.isNotEmpty(stuId)){
               student.setStuId(Integer.parseInt(stuId));
          }

          Connection con=null;
          try {
               con=dbUtil.getCon();
               int saveNums=0;
               JSONObject result=new JSONObject();
               if(StringUtil.isNotEmpty(stuId)){
                    saveNums=studentDao.studentModify(con, student);
               }else{
                    saveNums=studentDao.studentAdd(con, student);
               }
               if(saveNums>0){
                    result.put("success", "true");
               }else{
                    result.put("success", "true");
                    result.put("errorMeg", "删除失败");
               }
               ResponseUtil.write(response, result);
          } catch (Exception e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
          }finally{
               try {
                    dbUtil.closeCon(con);
               } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
               }
          }

     封装student
     public Student(String stuNo, String stuName, String sex, Date date,
               int gradeId, String email, String stuDesc) {
          super();
          this.stuNo = stuNo;
          this.stuName = stuName;
          this.sex = sex;
          this.birthday = date;
          this.gradeId = gradeId;
          this.email = email;
          this.stuDesc = stuDesc;
     }

     字符串转日期
     public static Date formatString(String str,String format) throws Exception{
          SimpleDateFormat sdf=new SimpleDateFormat(format);
          return sdf.parse(str);
     }
      日期转字符串
      public static String formatDate(Date date,String format){
          String result="";
          SimpleDateFormat sdf=new SimpleDateFormat(format);
          if(date!=null){
               result=sdf.format(date);
          }
          return result;
     }

4、修改web.xml
<servlet>
    <servlet-name>studentSaveServlet</servlet-name>
    <servlet-class>com.java1234.web.StudentSaveServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>studentSaveServlet</servlet-name>
    <url-pattern>/studentSave</url-pattern>
  </servlet-mapping> 

5、前端（略）

6、email验证
     validType="email"

6、隐藏列
<th field="gradeId" width="100" align="center" hidden="true">班级ID</th>

7、重置
      function resetValue(){
                    $('#stuNo').val("");
                    $('#stuName').val("");
                    $('#sex').combobox("setValue","");
                    $('#bbirthday').datebox("setValue","");
                    $('#gradeId').combobox("setValue","");
                    $('#email').val("");
                    $('#stuDesc').val("");
               }

8、关闭
            function closeStudentDialog() {
                    $("#dlg").dialog("close");
                    resetValue();
               }

9、添加
      function saveStudent(){
                    $("#fm").form("submit",{
                         url:url,
                         onSubmit:function(){
                              if($('#sex').combobox("getValue")==""){
                                   $.messager.alert("系统提示","请选择性别");
                                   return false;
                              }
                              if($('#gradeId').combobox("getValue")==""){
                                   $.messager.alert("系统提示","请选择所属班级");
                                   return false;
                              }
                              return $(this).form("validate");
                         },
                         success:function(result){
                              if(result.errorMsg){
                                   $.messager.alert("系统提示",result.errorMsg);
                                   return;
                              }else{
                                   $.messager.alert("系统提示","保存成功");
                                   resetValue();
                                   $("#dlg").dialog("close");
                                   $("#dg").datagrid("reload");
                              }
                         }
                    });
               }

10、修改前端
            function openStudentModifyDialog(){
                    var selectedRows=$("#dg").datagrid('getSelections');
                    if(selectedRows.length!=1){
                         $.messager.alert("系统提示","请选择一条要编辑的数据！");
                         return;
                    }
                    var row=selectedRows[0];
                    $("#dlg").dialog("open").dialog("setTitle","编辑学生信息");
                    $("#fm").form("load",row);
                    url="studentSave?stuId="+row.stuId;
               }

11、关联判断操作
     在删除班级时判断班级下面是否有人？
     public boolean getStudentByGradeId(Connection con,String gradeId)throws Exception{
          String sql="select * from t_student where gradeId=?";
          PreparedStatement pstmt=con.prepareStatement(sql);
          pstmt.setString(1, gradeId);
          ResultSet rs=pstmt.executeQuery();
          if(rs.next()){
               return true;
          }else{
               return false;
          }
     }

     String str[]=delIds.split(",");
               for(int i=0;i<str.length;i++){
                    boolean f=studentDao.getStudentByGradeId(con, str[i]);
                    if(f){
                         result.put("errorIndex", i);
                         result.put("errorMsg", "班级下面有学生,不能删除!");
                         ResponseUtil.write(response, result);
                         return;
                    }
               }

     function deleteGrade(){
          var selectedRows=$("#dg").datagrid('getSelections');
          if(selectedRows.length==0){
               $.messager.alert("系统提示","请选择要删除的数据！");
               return;
          }
          var strIds=[];
          for(var i=0;i<selectedRows.length;i++){
               strIds.push(selectedRows[i].id);
          }
          var ids=strIds.join(",");
          $.messager.confirm("系统提示","您确认要删掉这<font color=red>"+selectedRows.length+"</font>条数据吗？",function(r){
               if(r){
                    $.post("gradeDelete",{delIds:ids},function(result){
                         if(result.success){
                              $.messager.alert("系统提示","您已成功删除<font color=red>"+result.delNum+"</font>条数据!");
                              $("#dg").datagrid("reload");
                         }else{
                              $.messager.alert("系统提示",'<font color=red>'+selectedRows[result.errorIndex].gradeName+'</font>'+result.errorMsg);
                         }
                    },"json");
               }
          });
     }