个人作业二

多条件查询的实现

后台

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        request.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=utf-8"); 
        dao yidao=new dao();
        List<info>list = new ArrayList<info>();
        String p[] = new String[10];//获得条件
        String s[] = new String[10];//获得内容
        String g[] = new String[10];//获得关系
        String f[] = new String[10];//获得精确或者模糊
        String number = null;

        //String number1 = null;
        number=request.getParameter("number1");
        //number1=request.getParameter("number2");
        int n = Integer.parseInt(number);//接收条件的个数
        System.out.println("条件数"+n);
        //int n1 = Integer.parseInt(number1);
        for(int i=1;i<=n;i++)
        {
            p[i]= (String) request.getParameter("s"+i);
            s[i]=(String)request.getParameter("shuru"+i);
            f[i]=(String)request.getParameter("c"+i);
            System.out.println("精确还是模糊"+f[i]);
            System.out.println("条件"+p[i]);
            System.out.println("输入"+s[i]);
            if(p[i].equals("论文编号")){
                p[i] = "workId";
            }else if(p[i].equals("题目")){
                p[i] = "head";
            }else if(p[i].equals("关键词")){
                p[i] = "word";
            }else if(p[i].equals("作者")){
                p[i] = "writer";
            }
        }
        
        for(int i=1;i<n;i++)
        {
            g[i]=(String) request.getParameter("g"+i);
            if(g[i].equals("且")) {
                g[i]="and";
            }else if(g[i].equals("或")) {
                g[i]="or";
            }
            System.out.println("且或"+g[i]);
        }
        
        String sql="where ";
        for(int i=1;i<n;i++)
        {
            if(s[i].equals(""))
            {
                continue;
            }
            if(f[i].equals("精确"))
            {
                sql=sql+p[i]+"='"+s[i]+"'"+" "+g[i]+" ";
            }else if(f[i].equals("模糊"))
            {
                sql=sql+p[i]+" "+"LIKE"+" "+"'%"+s[i]+"%'"+" "+g[i]+" ";
            }
            
        }
        if(f[n].equals("精确")) {
            sql = sql + p[n]+"="+"'"+s[n]+"'";    
        }else {
            sql = sql + p[n]+" "+"LIKE"+" "+"'%"+s[n]+"%'";    
        }

        if(n==1&&s[1].equals(""))
        {
            System.out.println("什么也没传！");
            sql="";
        }
        list = yidao.loadview(sql);
            if(list.size()!=0) {
                Gson gson=new Gson();
                    String json=gson.toJson(list);
                    System.out.print(json);
                    response.getWriter().write(json);            
                    request.setAttribute("course11",list); 
        request.setAttribute("message", "查询成功");
        System.out.print("查询 成功");
            request.getRequestDispatcher("main.jsp").forward(request,response);
            }
            else {
                request.setAttribute("message", "查询失败");
                request.getRequestDispatcher("main.jsp").forward(request,response);
            }        
    }

前端

<script>
var i=1;
var j=1;
document.getElementById('number1').value=i;
document.getElementById('number2').value=j;
function demoDisplay(){
    if(document.getElementById("p2").style.display=="none"){
        i++;
        j++;
        document.getElementById("p2").style.display="inline";//inline是显示出来内容，none是不显示出来内容
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
//         alert(i);
//         alert(j);
        return;
    }else if(document.getElementById("p3").style.display=="none")
        {
            i++;
            j++;
            document.getElementById("p3").style.display="inline";
            document.getElementById('number1').value=i;
            document.getElementById('number2').value=j;
//             alert(i);
//             alert(j);
            return;
        }else if(document.getElementById("p4").style.display=="none")
        {
            i++;
            j++;
            document.getElementById("p4").style.display="inline";
            document.getElementById('number1').value=i;
            document.getElementById('number2').value=j;
//             alert(i);
//             alert(j);
            return;
        }else if(document.getElementById("p5").style.display=="none")
        {
            i++;
            j++;
            document.getElementById("p5").style.display="inline";
            document.getElementById('number1').value=i;
            document.getElementById('number2').value=j;
//             alert(i);
//             alert(j);
            return;
        }
        else if(document.getElementById("p6").style.display=="none")
        {
            i++;
            j++;
            document.getElementById("p6").style.display="inline";
            document.getElementById('number1').value=i;
            document.getElementById('number2').value=j;
//             alert(i);
//             alert(j);
            return;
        }
        else if(document.getElementById("p7").style.display=="none")
        {
            i++;
            j++;
            document.getElementById("p7").style.display="inline";
            document.getElementById('number1').value=i;
            document.getElementById('number2').value=j;
//             alert(i);
//             alert(j);
            return;
        }
}
function demoVisibility(){
     if(document.getElementById("p7").style.display=="inline")
    {
        i--;
        j--;
        document.getElementById("p7").style.display="none";
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
        //System.out.println("i:"+i+"j"+j);
        return;
    }
    else if(document.getElementById("p6").style.display=="inline")
    {
        i--;
        j--;
        document.getElementById("p6").style.display="none";
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
        //System.out.println("i:"+i+"j"+j);
        return;
    }
else if(document.getElementById("p5").style.display=="inline")
    {
        i--;
        j--;
        document.getElementById("p5").style.display="none";
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
        //System.out.println("i:"+i+"j"+j);
        return;
    }else if(document.getElementById("p4").style.display=="inline")
    {
        i--;
        j--;
        document.getElementById("p4").style.display="none";
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
        //System.out.println("i:"+i+"j"+j);
        return;
    }else if(document.getElementById("p3").style.display=="inline")
    {
        i--;
        j--;
        document.getElementById("p3").style.display="none";
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
        //System.out.println("i:"+i+"j"+j);
        return;
    }else if(document.getElementById("p2").style.display=="inline")
    {
        i--;
        j--;
        document.getElementById("p2").style.display="none";
        document.getElementById('number1').value=i;
        document.getElementById('number2').value=j;
        //System.out.println("i:"+i+"j"+j);
        return;
    }
}
</script>

//其中之一
<div id="p1">
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <select name="g22" style="visibility:hidden" class="slect">
    <option value="且">且</option>
    <option value="或">或</option>
    </select>
    <select name="s1" class="option">
    <option>题目</option>
    <option>作者</option>
    <option>论文编号</option>
    <option>关键词</option>
    </select>
    <input type="text" name="shuru1" class="input" value="" />
    <select name="c1" class="option">
    <option>精确</option>
    <option>模糊</option>
    </select>
    <button type="button" onclick="demoDisplay()" class="button"><i class="layui-icon">+</i></button>
    <button type="button" onclick="demoVisibility()" class="button"><i class="layui-icon">-</i></button>
    <br>
</div>

<thead>
   
    <tr>
      <th scope="col">题目</th>
      <th scope="col">作者</th>
      <th scope="col">发表日期</th>
      <th scope="col">原文链接 </th>
    </tr>
  </thead>
  <tbody id="list"> 
      
      <c:forEach items="${course11}" var="course1">
      <tr>
          <th>${course1.head }</th>
          <th>${course1.writer }</th>
          <th>${course1.date }</th>
          <th><a href="${course1.line}">${course1.line}</a></th>
        </tr>
        </c:forEach>
 
  </tbody>