如何检查我的comboobx值是否已经插入,如果它已经插入数据库中,则属性值在列表中不可见

本文关键字:插入 属性 何检查 列表 数据库 是否 comboobx 检查 如果 我的 | 更新日期: 2023-09-27 18:22:23

我有一个奇怪的问题,
我正在使用win-form,它是用c进行编码的。。和sql服务器
在一个表单中,我有一个由数据库收集数据的组合框(比如1)
然后我必须将该特定值/成员的详细信息插入另一个数据库(例如2)
在这里,我的问题提出了,一旦我的组合框中的任何值被插入到第二个数据库中,该特定值/成员就不应该在同一天的下一次出现在组合框中
当然,这里我使用的是日期时间选择器
这里我使用以下代码。。。当然这是错误的。。请帮我

 SqlCommand cmd1 = new SqlCommand("select employee_id,Empployee_Name,date from dailyattendance", cn);
       SqlDataReader sdr;
       DataTable dt = new DataTable();
       sdr = cmd1.ExecuteReader();

       if (sdr.Read())
       {
           string employeeid = (string)sdr["employee_id"];
           string employeename = (string)sdr["Empployee_Name"];
           string date = (string)sdr["date"];

           try
           {
               //cn.Open();
               SqlCommand cmd = new SqlCommand("select employee_id,employee_name from Employee_Details", cn);
               SqlDataReader sdr1;
               DataTable dt1=new DataTable();
               sdr1 = cmd.ExecuteReader();
               dt1.Load(sdr1);
               if (sdr1.Read())
               {
                   string date1=dateTimePicker1.Value.ToString("dd/MM/yyyy");
                   if ()//here the main problem
                   {
                       string employeeid1 = (string)sdr1["employee_id"];
                       string employeename1 = (string)sdr1["employee_name"];
                       comboBox1.DisplayMember = employeeid1;
                       comboBox1.DisplayMember = employeename1;
                       comboBox1.DataSource=dt1;
                       cn.Close();
                   }
               }

如何检查我的comboobx值是否已经插入,如果它已经插入数据库中,则属性值在列表中不可见

ConnectionStringSettings consettings = ConfigurationManager.ConnectionStrings["attendancemanagement"];
       string connectionString = consettings.ConnectionString;
       SqlConnection cn = new SqlConnection(connectionString);
       cn.Open();
       try
       {
           string dtp = dateTimePicker1.Value.ToString("dd/MM/yyyy");
           string query = "select employee_id,employee_name,image_of_employee,image_path from Employee_Details where employee_id not in (select employee_id from dailyattendance where date = '" + dtp + "')";//Here added a new query which is working
           SqlCommand cmd = new SqlCommand(query, cn);
           SqlDataReader dtr;
           dtr = cmd.ExecuteReader();
            DataTable dt = new DataTable();
            dt.Load(dtr);
           foreach (DataRow row in dt.Rows)
           {
               var name = (string)row["employee_name"];
               row["employee_name"] = name.Trim();
           }
            comboBox1.ValueMember = "employee_id";
            comboBox1.DisplayMember = "employee_name";
            listBox1.ValueMember = "employee_id";
            listBox1.DisplayMember = "employee_name";            
            comboBox1.DataSource = dt;
            listBox1.DataSource = dt;
            comboBox1.SelectedItem = null;
            listBox1.SelectedItem = null;
           cn.Close();
       }
       catch (System.Exception ex)
       {
           MessageBox.Show(ex.Message);
       }

简单地在查询中添加了一些可行的逻辑