How to count condition datagrid?

Question

I have table datagridview i want count people in grade and when cilck button count is show messagebox  A=3 B=1 C1  how to ?? I can't do it. help me please :( thank

Satyapriya Nayak · Answer

Hi pawinee using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Data.OleDb; namespace Grade_Count { public partial class Form1 : Form { string ConnectionString = System.Configuration.ConfigurationSettings.AppSettings[dsn]; OleDbCommand com; OleDbDataAdapter oledbda; string str; DataSet ds; public Form1() { InitializeComponent(); } private void Form1_Load(object sender EventArgs e) { OleDbConnection con = new OleDbConnection(ConnectionString); con.Open(); str = select * from test; com = new OleDbCommand(str con); oledbda = new OleDbDataAdapter(com); ds = new DataSet(); oledbda.Fill(ds test); dataGridView1.DataMember = test; dataGridView1.DataSource = ds; con.Close(); } private void btn_count_Click(object sender EventArgs e) { OleDbConnection con = new OleDbConnection(ConnectionString); con.Open(); str = SELECT COUNT(id) AS Total grade FROM test GROUP BY grade; com = new OleDbCommand(str con); oledbda = new OleDbDataAdapter(com); ds = new DataSet(); oledbda.Fill(ds test); dataGridView2.DataMember = test; dataGridView2.DataSource = ds; con.Close(); } } } Thanks

Senthilkumar · Answer

Hi If you read from the database then definitely you will be having DataSet. Then you can use the DataSet1.Table[0]; Usually if you do not have any data in the table and you are trying to bind the result.. SELECT ID Grade FROM Students It may not have any record in the sql server  still you can bind to the DataGridView. It will have the empty data grid.

Senthilkumar · Answer

Hi You can use the following LINQ to group by count. if you can use LINQ then the groupby clause will do the aggregation for you. // this is your datatable DataTable table = new DataTable(); table.Columns.Add(ID typeof(int)); table.Columns.Add(Grade typeof(string)); //insert your data table.Rows.Add(1A); table.Rows.Add(2B); table.Rows.Add(3C); table.Rows.Add(4A); table.Rows.Add(5A); table.Rows.Add(6B); table.Rows.Add(7B); table.Rows.Add(8D); table.Rows.Add(9A); // query with LINQ var query = from row in table.AsEnumerable() group row by row.Field (Grade) into oGrades orderby oGrades.Key select new { Name = oGrades.Key CountOfGrades = oGrades.Count() }; // print result string strMsg = string.Empty; foreach (var grade in query) { //int cnt = grade.CountOfGrades; strMsg += string.Format(
{0} = {1} grade.Namegrade.CountOfGrades); } MessageBox.Show(strMsg); I have tested and this is working fine as you expected.

pawinee mahantamak · Answer

Thank for your advice :D

pawinee mahantamak · Answer

thank Senthilkumar. If i don't insert new data. how to connect datagridview? (I use ADO.net oleDb) I never use linq but i will try