How to show error message

public DataView GetProductByID(string name ) 

{ 

using (SqlConnection conn = new SqlConnection(connstring))  

{ 

//string products = @"select*from TblName where name ='" + name + "'"; 

//SqlDataAdapter da = new SqlDataAdapter(products, conn);
 //DataSet ds = new DataSet();    conn.Open(); 
// da.Fill(ds); return ds.Tables[0].DefaultView; 
//------------ if LINQ otherwise comment this and use above----------------------//

var products= from TblName  in customers where cust.City == '" + name + "'"   ;                          select cust;
foreach(string s in products){

    if(s!=""){//show what do you want}

     else{

Label1.ForeGround = System.Colors.Color.Red;
Label1.Text = "No Record found!" ;

}

}

//------------------- end LINQ------------//

} 

}

DataView dvproduct = new DataView(); 

dvproduct = objManageStore.GetProductByID (Name);

if(dvproduct .Table.Rows.Count==0)

{

//Your Error Message

Label1.ForeGround = System.Colors.Color.Red;

Label1.Text = "No Record found!" ;

}

else{

//your execution showing code

}

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