C# 对数据库增删改查 求助 下载附件求解决 急急急急

zhonghxh

能对性别做出正确的操作 ，生日显示年月日

zhonghxh

强烈支持楼主ing……

站长苏飞

你这代码写的实在没法改，你还是看看我的宿舍管理系统吧，看懂一个就行了。

[C#] 纯文本查看 复制代码

using Model;
using System;
using System.Collections.Generic;
using System.Data;
using System.Linq;
using System.Text;

namespace Dal
{
  public  class studentsDal
    {
        public static students[] QueryAll()
        {
            string sql = "select * from students;";
            DataTable dt = SqlHelp.QueryBySql(sql);
            students[] result = new students[dt.Rows.Count];
            int i = 0;
            foreach (DataRow dr in dt.Rows)
            {
                students students = new students();
                students.id = Int32.Parse(dr["id"].ToString());
                students.name = dr["name"].ToString();
                students.sex = dr["sex"].ToString();
                students.code = dr["code"].ToString();
                students.birthday = DateTime.Parse(dr["birthday"].ToString());
                students.mobile = dr["mobile"].ToString();
                students.nativep = dr["nativep"].ToString();

                result[i] = students;
                i++;
            }
            return result;
        }

        public static students[] Find(string key)
        {
            string sql = "select * from students where id like '{0}' or name like '{0}' or sex like '{0}' or code like '{0}' or birthday like '{0}' or mobile like '{0}' or natavep like '{0}'";
            sql = string.Format(sql, key);
            DataTable dt = SqlHelp.QueryBySql(sql);
            students[] result = new students[dt.Rows.Count];
            int i = 0;
            foreach (DataRow dr in dt.Rows)
            {
                students students = new students();
                students.id = Int32.Parse(dr["id"].ToString());
                students.name = dr["name"].ToString();
                students.sex = dr["sex"].ToString();
                students.code = dr["code"].ToString();
                students.birthday = DateTime.Parse(dr["birthday"].ToString());
                students.mobile = dr["mobile"].ToString();
                students.nativep = dr["nativep"].ToString();

                result[i] = students;
                i++;
            }
            return result;
        }
        public static Boolean Update(students students)
        {
            String sql = "update students set name = '{0}', sex = '{1}', code = '{2}', birthday = '{3}', mobile = '{4}', nativep = '{5}' where id = '{6}'";
            sql = String.Format(sql, students.id, students.name, students.sex, students.code, students.birthday, students.mobile, students.nativep);
            Boolean result = SqlHelp.Excute(sql);
            if (result == true)
            {
                return true;
            }
            else
            {
                return false;
            }
            //return result;
        }

        public static Boolean Insert(students students)
        {
            String sql = "insert into students(id, name, sex, code, birthday, mobile, nativep) values('{0}','{1}','{2}', '{3}', '{4}', '{5}', '{6}')";
            sql = String.Format(sql, students.id, students.name, students.sex, students.code, students.birthday, students.mobile, students.nativep);
            Boolean result = SqlHelp.Excute(sql);
            if (result == true)
            {
                return true;
            }
            else
            {
                return false;
            }
            //return result;
        }

        public static Boolean Delete(string key)
        {
            string sql = "delete from students where id =" + key;
            Boolean result = SqlHelp.Excute(sql);
            if (result == true)
            {
                return true;
            }
            else
            {
                return false;
            }
            //return result;
        }
    }
}

代码毫无章法和套路
呵呵
id like '{0}' or name like '{0}' or sex like '{0}' or code like '{0}' or birthday like '{0}' or mobile like '{0}' or natavep like '{0}
那里用得着这么多啊，
你需要那个就写那个就是了，不用把所有的字段都加上
natavep 这个好像写错了吧。
你只写一个name like '{0}' 就行了吧
而且包含是这样写的
  string sql = "select * from students where  name like '%{0}%' ";

这样就有数据了，
其他的你参考这个修改下吧

站长苏飞

[C#] 纯文本查看 复制代码

  public static students[] Find(string key, string value)
        {
            string sql = "select * from students where  " + key + " like '%" + value + "%' ";
            DataTable dt = SqlHelp.QueryBySql(sql);
            students[] result = new students[dt.Rows.Count];
            int i = 0;
            foreach (DataRow dr in dt.Rows)
            {
                students students = new students();
                students.id = Int32.Parse(dr["id"].ToString());
                students.name = dr["name"].ToString();
                students.sex = dr["sex"].ToString();
                students.code = dr["code"].ToString();
                students.birthday = DateTime.Parse(dr["birthday"].ToString());
                students.mobile = dr["mobile"].ToString();
                students.nativep = dr["nativep"].ToString();

                result[i] = students;
                i++;
            }
            return result;
        }

调用修改成这样第一个查询功能就算是完了

[C#] 纯文本查看 复制代码

   private void button1_Click(object sender, EventArgs e)
        {
            string value = textBox1.Text.ToString();
            string key = comboBox1.Text;
            students[] flower = Dal.studentsDal.Find(key, value);
            dataGridView1.DataSource = flower;
        }

zhonghxh

哦哦 谢谢了

站长苏飞

能出来没有现在

zhonghxh

没有哦 不会弄 你的源代码居然是中文

站长苏飞

zhonghxh 发表于 2014-1-2 15:30
没有哦 不会弄 你的源代码居然是中文

那个时候能写出来那样的功能已经感觉很不错了，我那时候还在大二，呵呵

zhonghxh

我现在大二  你现在在干啥啊

站长苏飞

zhonghxh 发表于 2014-1-2 15:36
我现在大二  你现在在干啥啊

那看你现在写的代码，还没我们大一时学的好呢。呵呵
上班，打理这个网站，还是解决你的问题吧