c# - Update Datagridview From Another Form -

first should saw link :

how refresh datagridview when closing child form?

and did this: (i have datagridview in form1) form1:

                public void filldatagridview(datatable dt1)             {                     bindingsource1.datasource = dt1;                     bindingsource1.resetbindings(false);                     datagridview1.datasource = bindingsource1;                     //here checked number of rows of dt1 , shows correct value             } 

form2:

           sqlconnection cnn = new sqlconnection(@"my connection string");             private form1 handled_frm1;             public form2(form1 frm1)             {                     initializecomponent();                  handled_frm1 = frm1;             }                 private void textbox1_textchanged(object sender, eventargs e)                      {                         dt.clear();                         using (sqlcommand cmd =cnn.createcommand())                         {                             if (cnn.state == connectionstate.closed)                             {                                 cnn.open();                             }                             cmd.commandtype = commandtype.storedprocedure;                             cmd.connection = cnn;                             cmd.commandtext = "spsearchcustomerbyname";                             sqlparameter inparam1 = cmd.parameters.addwithvalue("@name", textbox1.text);                             inparam1.direction = parameterdirection.input;                             dap.selectcommand = cmd;                             dap.fill(dt);                              handled_frm1.filldatagridview(dt);                         } 

but value of datagridview not change!

edited:

i wanted test if can clear datagrid view or not,so changed filldatagridview :

                public void filldatagridview(datatable dt1)             {                     dt.clear();                     datagridview1.columns.clear();                     datagridview1.datasource = null;                     datagridview1.refresh();             } 

but not clear datagridview1!!!

i used mistakenly incorrect instance of form1!!

in form1,there button when click it,it shows form2.i wrote code in click event of it:

form1 frm1=new form1(); form2 frm2=new form2(frm1); 

and incorrect,because made additional instance of form1.

and change code this:

form2 frm2=new form2(this);