Create, Insert, Search, Delete in DataTable

//Create DataTable and Define its Fields (Cloumns)

DataTable dt = new DataTable();

dt.Columns.Add("ItemId",typeof(int));

dt.Columns.Add("Item",typeof(string));

dt.Columns.Add("Qty",typeof(float));

dt.Columns.Add("Category_Name", typeof(string));

//Fetch Data from DataBase and Insert into DataTable

DataSet dstmp = new DataSet();

query = "SELECT  *  FROM  vw_ItemDet";

SqlDataAdapter adp = new SqlDataAdapter(query, con);

adp.Fill(dstmp);

dt = dstmp.Tables[0];

//Insert Data from WebForm -:

 DataTable dt = (DataTable)ViewState["Dt"];

 DataRow dtdr = dt.NewRow();

 dtdr["ItemId"]=ddlOtherItem.SelectedValue;

 dtdr["Item"]=ddlOtherItem.SelectedItem.Text;

 dtdr["Qty"] = txtQty.Text;

 dt.Rows.Add(dtdr);

//Store values of DataTable in  ViewState for further use.Basically its helpful if you have to use  this table value later.

ViewState["dtable"] = dt;

//Retrieve value from ViewState

DataTable VWTempDTable=new DataTable();

VWTempDTable = (DataTable)ViewState["dtable"];

//Insert Values from one DataTable to Another based on some condition..-:

string cond = "Category_Name='" + ViewState["sad"] + "'";

DataRow[] foundRows;

foundRows = VWTempDTable.Select(cond);

foreach (DataRow row in foundRows)

{

            VWTempSecond.ImportRow(row); ///VWTempSecond is another DataTable

}

//Delete Rows from DataTable -:

VWTempSecond.Rows[Convert.ToInt32(s)].Delete();