How Do I Extract Data from a DataTable?

A stroll through data rows

When your needs are more Spartan and you crave the control of manually strolling through rows:

foreach (DataRow row in dataTable.Rows)
{
    var columnValue = row["YourColumnName"].ToString();
    // How about that tasty column value? Yum!
}
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See? foreach is your humble servant, trudging through each and every DataRow. And when you whisper the column names (row["ColumnName"].ToString()), it fetches the value for you. Loyal as a golden retriever 🐶.

Type-fu with Field<T>

No one likes those pesky runtime errors! Keep code tightrope-walking with the Field<T> method:

foreach (DataRow row in dataTable.Rows)
{
    int id = row.Field<int>("ID");
    string name = row.Field<string>("Name");
    DateTime? dateOfBirth = row.Field<DateTime?>("DateOfBirth");
    // Mmm... I love strongly-typed variables in the morning. 😎 
}
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Check that out! With Field<T>, you can handle nullable fields (DateTime?) and strongly-typed (int, string) like a champ!

Specific row and column 101

When you only need a particular bit of data like a plump cherry from the pie:

string specificData = dataTable.Rows[rowIndex]["YourColumnName"].ToString();
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Oh, see that rowIndex? That's the spot where the cherry lies. YourColumnName is your cherry-picker 🍒.

Dealing with the crowd: Large DataTables

Got a large crowd of data? DataReader to the rescue:

using (var command = new SqlCommand(query, connection))
{
    using (var reader = command.ExecuteReader())
    {
        while (reader.Read())
        {
            string item = reader["ColumnName"].ToString();
            // Look ma, no DataTable! 👀
        }
    }
}
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Post reading, call it a day and kindly ask SqlDataReader to close up, freeing your resources.

ORM: A bigger hammer

For bigger tasks, there are bigger tools. ORMs like Entity Framework or nHibernate provide strongly-typed and efficient solutions.

var items = context.TableName.ToList();
foreach(var item in items)
{
    Console.WriteLine(item.PropertyName);
    // ORM + LINQ = 🍹 on the beach!
}
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Web controls: Serving pancakes hot!

Hot pancakes (DataTable data) to web controls like GridView, Repeater or DataList:

GridView.DataSource = dataTable;
GridView.DataBind();
// Data pancakes ready to eat! 🥞
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How many pancakes? Counting rows

Need to count the pancakes? One could simply:

int numRows = dataTable.Rows.Count;
// Num. of Pancakes == Num. of Happiness! 😊
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