# c# – How to iterate through a DataTable

## The Question :

150 people think this question is useful

I need to iterate through a DataTable. I have an column there named ImagePath.

When I am using DataReader I do it this way:

SqlDataReader dr = null;
{
TextBox1.Text = dr["ImagePath"].ToString();
}



How can I achieve the same thing using DataTable?

• dr.Read() reads row by row from the network buffer, not row by row from the database.There is only one fetch from the database. Hence reading from a datatable is not going offer any performance gain.

299 people think this answer is useful
DataTable dt = new DataTable();

foreach(DataRow row in dt.Rows)
{
TextBox1.Text = row["ImagePath"].ToString();
}



…assumes the connection is open and the command is set up properly. I also didn’t check the syntax, but it should give you the idea.

33 people think this answer is useful
foreach (DataRow row in myDataTable.Rows)
{
Console.WriteLine(row["ImagePath"]);
}



I am writing this from memory.
Hope this gives you enough hint to understand the object model.

DataTable -> DataRowCollection -> DataRow (which one can use & look for column contents for that row, either using columnName or ordinal).

-> = contains.

22 people think this answer is useful

You can also use linq extensions for DataSets:

var imagePaths = dt.AsEnumerble().Select(r => r.Field<string>("ImagePath");
foreach(string imgPath in imagePaths)
{
TextBox1.Text = imgPath;
}



5 people think this answer is useful

The above examples are quite helpful. But, if we want to check if a particular row is having a particular value or not. If yes then delete and break and in case of no value found straight throw error. Below code works:

foreach (DataRow row in dtData.Rows)
{
if (row["Column_name"].ToString() == txtBox.Text)
{
// Getting the sequence number from the textbox.
string strName1 = txtRowDeletion.Text;

// Creating the SqlCommand object to access the stored procedure
// used to get the data for the grid.
string strDeleteData = "Sp_name";
SqlCommand cmdDeleteData = new SqlCommand(strDeleteData, conn);
cmdDeleteData.CommandType = System.Data.CommandType.StoredProcedure;

// Running the query.
conn.Open();
cmdDeleteData.ExecuteNonQuery();
conn.Close();

GetData();

dtData = (DataTable)Session["GetData"];
BindGrid(dtData);

lblMsgForDeletion.Text = "The row successfully deleted !!" + txtRowDeletion.Text;
txtRowDeletion.Text = "";
break;
}
else
{
lblMsgForDeletion.Text = "The row is not present ";
}
}


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