C＃combox显示项目和值 [英] C# combox display items and value

问题描述

我的组合框..



cbodept和cbocourse



我的数据库表..



tbldepartment [deptcode，dept_desc]

tblcourse [coursecode，course_desc，deptcode]



我想要的是：



1.在表单加载期间：在cbodept中显示所有dept_desc。



2 .cbodept值：我希望dept_desc作为保存到我的数据库的值。



2. cbodept_SelectedIndexChanged：我想在我的cbocourse中加载所有课程。



3. cbocourse值：我想将course_desc作为我的数据库中保存的值。



什么我试过了：

my combobox..

cbodept and cbocourse

my db tables..

tbldepartment[deptcode,dept_desc]
tblcourse[coursecode,course_desc,deptcode]

What i want:

1. During form load : display all dept_desc in cbodept.

2. cbodept value : i want dept_desc as value to be save to my db.

2. cbodept_SelectedIndexChanged : i want to load all courses in my cbocourse.

3. cbocourse value : i want course_desc as the value to be save in my db.

What I have tried:

private void loadDepartment()
        {
            try
            {
                SqlConnection cnn = new SqlConnection(cs.constring());
                DataSet ds = new DataSet();
                string getEmpSQL = "select deptcode from tbldepartment";
                SqlDataAdapter sda = new SqlDataAdapter(getEmpSQL, cnn);

                sda.Fill(ds);
                cbodept.DataSource = ds.Tables[0];
                cbodept.DisplayMember = ds.Tables[0].Columns[0].ToString();

            }
            catch(Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
        }

private void loadCourse()
        {
            try
            {
                SqlConnection cnn = new SqlConnection(cs.constring());
                DataSet ds = new DataSet();
                string getEmpSQL = "select coursecode from tblcourse where department= '" + cbodept.Text + "'";
                SqlDataAdapter sda = new SqlDataAdapter(getEmpSQL, cnn);

                sda.Fill(ds);
                cbocourse.DataSource = ds.Tables[0];
                cbocourse.DisplayMember = ds.Tables[0].Columns[0].ToString();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
        }

private void cbodept_SelectedIndexChanged(object sender, EventArgs e)
        {
            loadCourse();
        }

推荐答案

try
          {
              SqlConnection cnn = new SqlConnection(cs.constring());
              DataSet ds = new DataSet();
              string getEmpSQL = "select deptcode from tbldepartment";
              SqlDataAdapter sda = new SqlDataAdapter(getEmpSQL, cnn);

              sda.Fill(ds);
              cbodept.DataSource = ds.Tables[0].DefaultView;
              cbodept.DisplayMember = ds.Tables[0].Columns["deptcode "].ToString();
              cbodept.ValueMember = ds.Tables[0].Columns["deptcode "].ToString();


          }
          catch (Exception ex)
          {
              MessageBox.Show(ex.ToString());
          }

private void LoadDepartment()
{
     var dt = new DataTable();
     var conn = new SqlConnection(connectionString);
     var cmd = new SqlCommand("SELECT deptcode FROM tbldepartment",conn);
     var da = new SqlDataAdapter(cmd);
     dt.Clear();
     da.fill(dt);
     for(DataRow item in dt.Rows)
       {
          cbodept.Items.Add(item[0].ToString());
       }
} 

private void LoadCourse()
{
     var dt = new DataTable();
     var conn = new SqlConnection(connectionString);
       var cmd = new SqlCommand("SELECT coursecode FROM tblcourse WHERE    department='"+cbodept.Text+"'",conn);
     var da = new SqlDataAdapter(cmd);
     dt.Clear();
     da.fill(dt);
     for(DataRow item in dt.Rows)
       {
          cbocourse.Items.Add(item[0].ToString());
       }
}
private void cbodept_SelectedIndexChanged(object sender, EventArgs e)
        {
            loadCourse();
        }

这篇关于C＃combox显示项目和值的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！