How to refresh a datagrid in C# windows application after delete/insert/updation of records

Question

It is related to Datagrid in C# windows Applications: 1. When a row is deleted from a datagrid, it should be removed from the grid as well as from the database.It gets deleted from database but still visible on datagrid. I used datagrid.refresh but it did not work? How to do it? Basically how to refresh a datagrid after insertion/deletion/updation of records 2. When I try to navigate the records in datagrid after deletion/addition/updation of row, I get the following error message: "An Unhandled exception has occured in your application.......... Cannot Create a child list for field Test" Why it is so. I am writing the code below: Under Form_load event: cc=new Class1(); string ss="select * from test"; dt=cc.conn(ss); //dt is dataset dataGrid1.SetDataBinding(dt,"Test"); this.BindingContext[dt,"Test"].Position=0; under adding of new record: tring ins="Insert into test values("+aa+","+"'"+ss+"')"; dt=cc.conn(ins); dt.AcceptChanges(); MessageBox.Show("record added successfully"); Under Next record navigation: this.BindingContext[dt,"Test"].Position+=1; Under Previuos record navigation: this.BindingContext[dt,"Test"].Position-=1; How to handle this error?