C# .NET - check unique value before adding to DataTable

Hi friends
i have one datatable and i want i must contain unique value, i set:
dt.Columns[0].Unique = true;

now  value added on datatable form textbox, i want to prevent add duplicate value in datatable without loop,
so that unique value must be added in datatable
how can i do it, help me
Thanks

For this use this code-

string s = "primaryKeyValue";

DataRow foundRow = dataSet1.Tables["AnyTable"].Rows.Find(s);
if (foundRow != null) 
{
    MessageBox.Show("Already Exist"));
}
else
{
    //Add Value to DataTable
}

Try this code and let me know,

Try this way

DataRow[] dupRows =  myDataTable.Select("columnName1 like '%" + TextBox.Text + "%'");

If(dupRows!=null)
 {
   MessageBox.Show("This record is already present.")
 }

Regards

Use UNIQUE Constraint for table

The UNIQUE constraint uniquely identifies each record in a database table.

The UNIQUE and PRIMARY KEY constraints both provide a guarantee for uniqueness for a column or set of columns.

CREATE TABLE Persons
(
P_Id int NOT NULL UNIQUE,
LastName varchar(255) NOT NULL,
-----
-----
}

For Inserting unique value in database table, you are trying to get unique value in DataTable this approch is wrong, because if you check uniqueness in datatable and insert into database table but when next time same datatable contain unique rows but that row may be exists in table and when you insert it will be duplicate so I suggest you don't try this approach.

Datarow[] dr=Dt.Select("column="+textbox1.text);
if(dr.Length==0)// this means datatable doesnt contain that value
{
/// add the code to insert data
}

HI Vickey
this is working for my requirement, Thank u mery much

You always welcome.