Update a gridview when contact form is closing

Question

Hallo
Hope all are well.
I got a NewCompany form that uses a clickevent to open another form to fill in contact details.
But this then updates field in sql. I want to update the gridview with the new information when the contactform has been filled in.
I created a method to run which is populating the main form, I made it public so can access the method on the contactform.
below the code to update the gridview, this part is working when executing from the NewCompany.
The next code is when I done the update and want to update the form.
public void PopulateGridView()
CreateConnection();
try
con = new SqlConnection(constring);
cmd = new SqlCommand("Select CompanyDetailID, ContactID, Name, Surname, JobTitle, Cellphone, Landline, Extension, Email, Birthday, Notes " +
"from ContactDetails " +
"where CompanyDetailID = @SelectedSubDivID ",con);
cmd.Parameters.AddWithValue("@SelectedCompanyID", SelectCompanyID);
cmd.Parameters.AddWithValue("@SelectedSubDivID", SelectSubdivisionID);
sda = new SqlDataAdapter(cmd);
dt = new DataTable();
sda.Fill(dt);
dgContactInfo.DataSource = dt;
dgContactInfo.Columns[0].Visible = false;
dgContactInfo.Columns[1].Visible = false;
catch (Exception ex)
MessageBox.Show(ex.ToString());
finally
The code from the subform trying to execute the top part.
private void txtSave_Click(object sender, EventArgs e)
if (CheckEntryValidation())
MessageBox.Show("All Filled In");
if (ContactID == 0)
try
CreateConnection();
con = new SqlConnection(constring);
con.Open();
cmd = new SqlCommand("INSERT INTO ContactDetails (CompanyDetailID, Name, Surname, JobTitle, Cellphone, Landline, Extension, " +
"Email, Birthday, Notes) " +
"VALUES (@CompanyDetailIDs, @Names, @Surnames, @JobTitles, @Cellphones, @Landlines, @Extensions, " +
"@Emails, @Birthdays, @Notess) ", con);
cmd.Parameters.AddWithValue("@CompanyDetailIDs", DetailID);
cmd.Parameters.AddWithValue("@Names", this.txtName.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Surnames", this.txtSurname.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@JobTitles", this.txtJobTitle.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Cellphones", this.txtCellphone.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Landlines", this.txtLandline.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Extensions", this.txtExtension.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Emails", this.txtEmail.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Birthdays", dateOnly);
cmd.Parameters.AddWithValue("@Notess", this.txtNotes.Text.ToString().Trim());
cmd.ExecuteNonQuery();
MessageBox.Show("Succesfully added");
NewCompany Updgridview = new NewCompany();
Updgridview.PopulateGridView();
this.Close();
catch (Exception ex)
MessageBox.Show(ex.ToString());
finally
con.Close();
labjac

Answer 1

Hallo Fouad
Thanks for the reply, below the code extractions I tried. it complains about a Null reference not set as a object, (Please see pictures attached). I think I might be doing something wrong. please let me know what parts you need to assist.
Calling the ContactDetailsPopup form form the NewCompany form that got the gridview for updating:
private void txtAddContact_Click(object sender, EventArgs e)
if (SelectSubdivisionID != 0)
GridSelectDetailsID = SelectSubdivisionID;
GridSelectContactID = 0;
ContactDetailsPopup ContactPage = new ContactDetailsPopup(GridSelectContactID, GridSelectDetailsID);
ContactPage.Show();
else
MessageBox.Show("Please select Company and Sub Division first");
The Constructor (I think)..
private NewCompany UpdateMainView;
public ContactDetailsPopup(NewCompany Ncomp)
InitializeComponent();
UpdateMainView = Ncomp;
The Update and save:
private void txtSave_Click(object sender, EventArgs e)
if (CheckEntryValidation())
if (ContactID == 0)
try
CreateConnection();
con = new SqlConnection(constring);
con.Open();
cmd = new SqlCommand("INSERT INTO ContactDetails (CompanyDetailID, Name, Surname, JobTitle, Cellphone, Landline, Extension, " +
"Email, Birthday, Notes) " +
"VALUES (@CompanyDetailIDs, @Names, @Surnames, @JobTitles, @Cellphones, @Landlines, @Extensions, " +
"@Emails, @Birthdays, @Notess) ", con);
cmd.Parameters.AddWithValue("@CompanyDetailIDs", DetailID);
cmd.Parameters.AddWithValue("@Names", this.txtName.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Surnames", this.txtSurname.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@JobTitles", this.txtJobTitle.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Cellphones", this.txtCellphone.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Landlines", this.txtLandline.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Extensions", this.txtExtension.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Emails", this.txtEmail.Text.ToString().Trim());
cmd.Parameters.AddWithValue("@Birthdays", dateOnly);
cmd.Parameters.AddWithValue("@Notess", this.txtNotes.Text.ToString().Trim());
cmd.ExecuteNonQuery();
MessageBox.Show("Succesfully added");
UpdateMainView.PopulateGridViewWithParm(DetailID, ContactID);
this.Close();
catch (Exception ex)
MessageBox.Show(ex.ToString());
finally
con.Close();
The Update Gridview Method on the NewCompany Main page where the gridview is present.
public void PopulateGridViewWithParm(int CompanyID, int SubDivID)
int loc_SelectCompanyID = CompanyID;
int loc_SelectSubDivisionID = SubDivID;
CreateConnection();
try
con = new SqlConnection(constring);
cmd = new SqlCommand("Select CompanyDetailID, ContactID, Name, Surname, JobTitle, Cellphone, Landline, Extension, Email, Birthday, Notes " +
"from ContactDetails " +
"where CompanyDetailID = @SelectedSubDivID ", con);
cmd.Parameters.AddWithValue("@SelectedCompanyID", CompanyID);
cmd.Parameters.AddWithValue("@SelectedSubDivID", SubDivID);
sda = new SqlDataAdapter(cmd);
dt = new DataTable();
sda.Fill(dt);
dgContactInfo.DataSource = dt;
dgContactInfo.Columns[0].Visible = false;
dgContactInfo.Columns[1].Visible = false;
catch (Exception ex)
MessageBox.Show(ex.ToString());
finally
Please note that the updateGridview is working correctly when updated from the NewCompany page where the Gridview is present. 
Regards,
Jacques.
labjac