Reading DataSet

Question

How do I read data from a DataSet in WPF? I have a train schedule table with just 2 columns and I want to be able to read the departure times and calculate when the next train is leaving. For example, the time now is 12:29 and my application should tell me that next train will depart at 12:33.

I already googled left and right. I'm on .NET 3.5.

Answer 1

DataSet resembles database. DataTable resembles database table, and DataRow resembles a record in a table. If you want to add filtering or sorting options, you then do so with a DataView object, and convert it back to a separate DataTable object.

If you're using database to store your data, then you first load a database table to a DataSet object in memory. You can load multiple database tables to one DataSet, and select specific table to read from the DataSet through DataTable object. Subsequently, you read a specific row of data from your DataTable through DataRow. Following codes demonstrate the steps:

SqlCeDataAdapter da = new SqlCeDataAdapter(); DataSet ds = new DataSet(); DataTable dt = new DataTable();  da.SelectCommand = new SqlCommand(@"SELECT * FROM FooTable", connString); da.Fill(ds, "FooTable"); dt = ds.Tables["FooTable"];  foreach (DataRow dr in dt.Rows) {     MessageBox.Show(dr["Column1"].ToString()); } 

To read a specific cell in a row:

int rowNum // row number string columnName = "DepartureTime";  // database table column name dt.Rows[rowNum][columnName].ToString(); 

Answer 2

If ds is the DataSet, you can access the CustomerID column of the first row in the first table with something like:

DataRow dr = ds.Tables[0].Rows[0]; Console.WriteLine(dr["CustomerID"]);