菜品管理模块01

1、  编写菜品数据访问类

1. 获取菜品分类
2. 新增菜品（返回新增菜品ID号，为了给图片编号）

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Data;
using Models;

namespace DAL
{
    /// <summary>
    /// 菜品数据访问类
    /// </summary>
   public class DishService
    {
       /// <summary>
       /// 获取菜品分类
       /// </summary>
       /// <returns></returns>
       public List<DishCategroy> GetAllCategory()
       {
           string sql = "select CategoryId,CategoryName from DishCategory";
           List<DishCategroy> list = new List<DishCategroy>();
           SqlDataReader objReader = SQLHelper.GetReader(sql);
           while (objReader.Read()) 
           {
               list.Add(new DishCategroy()
               {
                   CategoryId = Convert.ToInt32(objReader["CategoryId"]),
                   CategoryName = objReader["CategoryName"].ToString().Trim()
               });
           }
           objReader.Close();
           return list;
       }

       /// <summary>
       /// 新增菜品（返回新增菜品ID号）
       /// </summary>
       /// <param name="objDish"></param>
       /// <returns></returns>
       public int AddDish(Dish objDish)
       {
           string sql = "insert into Dishes(DishName,UnitPirce,CategoryId)";
           sql += " values(@DishName,@UnitPirce,@CategoryId);select @@identity";
           SqlParameter[] param = new SqlParameter[]
           {
                  new SqlParameter("@DishName",objDish.DishName),
                  new SqlParameter("@UnitPirce",objDish.UnitPrice),
                  new SqlParameter("@CategoryId",objDish.CategoryId)
           };
           return Convert.ToInt32(SQLHelper.GetSingleResult(sql));  //返回自增号
       }

    }
}

2、页面载入后台程序编写

1.  编写“添加菜品”的后台下拉框填充程序
2. 判断是修改还是新增

3、按钮事件的编写

1. 数据验证
2. 封装对象
3. 提交数据
1. 提交菜品信息，并返回菜品编号
2. 上传图片（采用函数调用的方法，另编一个私有函数）
1. 判断是否有文件
2. 获取文件大小，判断文件大小是否符合要求
3. 获取图片的名称，并修改成规范的文件名
4. 上传图片

4.清空以前输入的内容

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Models;
using DAL;

namespace HotelWebProject.Adminhyl
{
    public partial class DishesPublish : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            { 
            //初始化菜品分类下拉框
                this.ddlCategory.DataValueField = "CategoryId";
                this.ddlCategory.DataTextField = "CategoryName";
                this.ddlCategory.DataSource = new DAL.DishService().GetAllCategory();
                this.ddlCategory.DataBind();
             }
           //判断是修改还是新增
            if (Request.QueryString["Operation"] == "0")  //如果是新增， 来自链接项<li><a href="/Adminhyl/Dishes/DishesPublish.aspx?Operation=0">添加菜品</a></li>
            {
                this.btnEdit.Visible = false; //编辑按钮不可见 
            }
            else 
            {
            
            }
            this.ltaMsg.Text = "";//ltaMsg可能会有一些信息，每次都清除一下
        }

        protected void btnPublish_Click(object sender, EventArgs e)
        {
            //数据验证
            if (this.txtDishName.Text.Trim().Length == 0)
            {
                this.ltaMsg.Text = "<script>alert('请输入菜品名称！')</script>";
                return;
            }
            if (this.ddlCategory.SelectedIndex == -1)
            {
                this.ltaMsg.Text = "<script>alert('请选择菜品分类！')</script>";
                return;           
            }
            if (this.txtUnitPrice.Text.Trim().Length==0)
            {
                this.ltaMsg.Text = "<script>alert('请输入菜品价格！')</script>";
                return;
            }
            if (!Common.DataValidate.IsInteger(this.txtUnitPrice.Text.Trim()))  //用正则表达式验证是否正整数
            {
                this.ltaMsg.Text = "<script>alert('菜品价格必须是整数！')</script>";
                return;
            }
            //封装对象
            Models.Dish objDish = new Dish()
            {
                DishName=this.txtDishName.Text.Trim(),
                UnitPrice=Convert.ToInt32(this.txtUnitPrice.Text.Trim()),
                CategoryId=Convert.ToInt32(this.ddlCategory.SelectedValue),//选中菜品分类所对应的ID
            };
            //提交数据
            try
            {
                if (this.btnPublish.Visible == true)   //如果是新增菜品
                {
                    if (!this.fulImage.HasFile)  //必须要选择图片(文件名不能为空)
                    {
                        this.ltaMsg.Text = "<script>alert('请选择菜品图片！')</script>";
                        return;
                    }
                    //提交菜品信息，并返回菜品编号
                    int dishId = new DishService().AddDish(objDish);
                    //上传图片
                    this.UploadImage(dishId);
                    this.ltaMsg.Text = "<script>alert('添加成功！')</script>";
                    //清空以前输入的内容
                    this.txtDishName.Text = "";
                    this.txtUnitPrice.Text = "";
                    this.ddlCategory.SelectedIndex = -1;

                }
            }
            catch (Exception ex)
            {
                this.ltaMsg.Text = "<script>alert('添加失败！" + ex.Message + "  ')</script>";
            }

        }
        /// <summary>
        /// 上传图片的函数
        /// </summary>
        /// <param name="dishId"></param>
        private void UploadImage(int dishId)
        { 
        //[1]判断是否有文件
            if (!this.fulImage.HasFile) return;
        //[2] 获取文件大小，判断文件大小是否符合要求
            double fileLength = this.fulImage.FileContent.Length / (1024.0 * 1024.0);
            if (fileLength > 2.0)
            {
                this.ltaMsg.Text = "<script>alert('图片最大不能超过2M')</script>";
                return;
            }
         //[3]获取图片的名称，并修改成规范的文件名
            string fileName = this.fulImage.FileName;
            if (fileName.Substring(fileName.LastIndexOf(".")).ToLower() != ".png")
            {
                this.ltaMsg.Text = "<script>alert('图片必须是png格式！')</script>";
                return;            
            }
            fileName = dishId + ".png";
         //[4]上传图片
            try
            {
                string path = Server.MapPath("~/Images/dish");
                this.fulImage.SaveAs(path + "/" + fileName);
            }
            catch (Exception ex)
            {
                this.ltaMsg.Text = "<script>alert('图片上传失败！" + ex.Message +  "  ')</script>";
            }
        }
    }
}