mysql - How to change the color of a cell of Datagridview by comparing the cell date with today's Date in C#.net? -

i new c#,this first project on c# language , backend mysql, stuck @ particular point ,i having form containing datagridview binded database value,in have column "tns_date" expiration date of product ,i want if tns_date greater current date background colour of particular cell should red in colured ,how ,please me this

i using winforms , till had tried

foreach (datagridviewrow row in tnsformdgv.rows) {     var                =  datetime.now;     var expirationdate     =  datetime.parse(row.cells[15].value.tostring());     var onemonthbefore     = expirationdate.adddays(-30);     if (now > onemonthbefore && < expirationdate)     {         row.defaultcellstyle.backcolor = color.yellow;     }     else if (now > expirationdate)     {         row.defaultcellstyle.backcolor = color.red;     } } 

when executing project getting error

object reference not set instance of object 

this whole code particular form please check getting wrong

public partial class tns_subscription : form {     public tns_subscription()     {         initializecomponent();         tnssubscriptionform();     }     private void tnsformbackbtn_click(object sender, eventargs e)     {         new form2().show();         this.hide();     }     public void tnssubscriptionform()     {         string constring = "datasource=localhost;port=3306;username=root;password=ajay";         mysqlconnection condatabase = new mysqlconnection(constring);         mysqlcommand cmddatabase = new mysqlcommand("select acmecmpdetails.cmp_number,acmecmpdetails.cmp_name,acmecmpdetails.cmp_adminid,acmecmpdetails.cmp_address1,acmecmpdetails.cmp_country1,acmecmpdetails.cmp_state1,acmecmpdetails.cmp_city1,acmecmpdetails.cmp_postalcode,acmecmpdetails.contact_person1,acmecmpdetails.landline_number1,acmecmpdetails.mobilenumber,acmecmpdetails.cntct_emailid,acmetally_detail.tallyserial_no,acmetally_detail.tally_release,acmetally_detail.tally_edition,acmetally_detail.tns_date,acmetally_detail.tally_prefpartner,acmetally_detail.tally_accountid acmesolutionsdatabase.acmecmpdetails inner join acmesolutionsdatabase.acmetally_detail on acmesolutionsdatabase.acmecmpdetails.tallyserial_no= acmesolutionsdatabase.acmetally_detail.tallyserial_no;", condatabase);           try         {             mysqldataadapter cddsda = new mysqldataadapter();             cddsda.selectcommand = cmddatabase;             datatable dbdataset = new datatable();             cddsda.fill(dbdataset);             bindingsource bsource = new bindingsource();             bsource.datasource = dbdataset;             tnsformdgv.datasource = bsource;             cddsda.update(dbdataset);             for(int i=0;i<tnsformdgv.rows.count;i++)             {                 if (convert.todatetime(tnsformdgv.rows[i].cells["tns_date"].value.tostring()) > system.datetime.now.date)                 {                      tnsformdgv.rows[i].cells["tns_date"].style.backcolor = system.drawing.color.red;                 }              }         }             catch (exception ex)         {              messagebox.show(ex.message);         }     } } 

thanks in advance

you this:

for(int i=0;i<mygridview.rows.count;i++) {     if (convert.todatetime(mygridview.rows[i].cells["tns_date"].value.tostring()) > system.datetime.now.date)     {         mygridview.rows[i].cells["tns_date"].style.backcolor = system.drawing.color.red;     } } 

it change backcolor of cell "tns_date" if value greater current date.

or can use index of column tns_date like:

if index of column tns_date 3, then:

for(int i=0;i<mygridview.rows.count;i++) {     if (convert.todatetime(mygridview.rows[i].cells[3].value.tostring()) > system.datetime.now.date)     {         mygridview.rows[i].cells[3].style.backcolor = system.drawing.color.red;     } } 

i hope solve problem.