1.查詢條件的封裝物件

頁面傳送條件到後臺的物件一般命名有vo

package com.bjpowernode.pojo.vo;

public class ProductInfoVo {
    //商品名稱
    private String pname;
    //商品型別
    private Integer typeid;
    //最低價格
    private Integer lprice;
    //最高價格
    private Integer hprice;
    //設定頁碼
    private Integer page=1;

    @Override
    public
 
 String toString() {
        return "ProductInfoVo{" +
                "pname='" + pname + '\'' +
                ", typeid=" + typeid +
                ", lprice=" + lprice +
                ", hprice=" + hprice +
                ", page=" + page +
                '}';
    }

    public String getPname() {
        
 
return pname;
    }

    public void setPname(String pname) {
        this.pname = pname;
    }

    public Integer getTypeid() {
        return typeid;
    }

    public void setTypeid(Integer typeid) {
        this.typeid = typeid;
    }

    public Integer getLprice() {
        return lprice;
    }

    
 
public void setLprice(Integer lprice) {
        this.lprice = lprice;
    }

    public Integer getHprice() {
        return hprice;
    }

    public void setHprice(Integer hprice) {
        this.hprice = hprice;
    }

    public Integer getPage() {
        return page;
    }

    public void setPage(Integer page) {
        this.page = page;
    }

    public ProductInfoVo(String pname, Integer typeid, Integer lprice, Integer hprice, Integer page) {
        this.pname = pname;
        this.typeid = typeid;
        this.lprice = lprice;
        this.hprice = hprice;
        this.page = page;
    }

    public ProductInfoVo() {
    }
}

2.mapper開發

<sql id="Base_Column_List" >
    p_id, p_name, p_content, p_price, p_image, p_number, type_id, p_date
  </sql>

 <select id="selectCondition" parameterType="com.bjpowernode.pojo.vo.ProductInfoVo" resultMap="BaseResultMap">
    select <include refid="Base_Column_List"></include>
    from product_info
    <!--拼接條件-->
    <where>
      <!--商品名稱不為空,拼接商品名稱模糊查詢-->
      <if test="pname != null and pname !=''">
        and p_name like '%${pname}%'
      </if>
      <!--商品型別不為空,拼接商品型別查詢條件-->
      <if test="typeid != null and typeid != -1">
        and type_id =#{typeid}
      </if>
      <!--如果最低價格不為空,最高價格為空,則查詢大於最低價格的所有商品-->
      <if test="(lprice != null and lprice != '') and (hprice == null or hprice == '')">
        and p_price &gt;= #{lprice}
      </if>
      <!--如果最高價格不為空,最低價格為空,則查詢小於最高價格的所有商品-->
      <if test="(hprice != null and hprice !='') and (lprice == null or lprice == '')">
        and p_price &lt;= #{hprice}
      </if>
      <!--如果最高和最低價格都不為空,則查詢介於最高價格和最低價格之間的所有商品-->
      <if test="(lprice !=null and lprice !='') and (hprice != null and hprice != '')">
        and p_price between #{lprice} and #{hprice}
      </if>
    </where>
    order by p_id desc
  </select>

3.業務邏輯層

@Override
    public List<ProductInfo> selectCondition(ProductInfoVo vo) {
        return productInfoMapper.selectCondition(vo);
    }

4.控制器開發

    //   多條件查詢功能實現
    @ResponseBody
    @RequestMapping("/condition")
    public void condition(ProductInfoVo vo, HttpSession session){
        List<ProductInfo> list = productInfoService.selectCondition(vo);
        session.setAttribute("list",list);
    }