Question

I am trying to create a binding source to my binding navigator that will be able to show all branches within a specific bank.

The statement that gets the datasource is as follows

branchMasterBindingSource.DataSource = Program.Kernel.Get<IBranchMasterService>().GetAllBranchMasters();

However, this pulls all branches regardless of the banks they belong to.

I need to know how to change this so that it gets AllBranchMasters where a field in the database (“U_bank_code”) is equals to a combobox named “cb_bank_code”

Extra code is below:

private void cb_bank_code_SelectedIndexChanged(object sender, EventArgs e)
       {    

           branchMasterBindingSource.DataSource = null;
           branchMasterBindingSource.DataSource = Program.Kernel.Get<IBranchMasterService>().GetAllBranchMasters();

           //clear textfields after input
           lbl_show_bank_name.Text = string.Empty;
           txt_branch_code.Text = string.Empty;
           txt_branch_name.Text = string.Empty;
           txt_swift_sort_code.Text = string.Empty;
           txt_address_1.Text = string.Empty;
           txt_address_2.Text = string.Empty;
           txt_comments.Text = string.Empty;

           var bankMasterService = Program.Kernel.Get<IBankMasterService>();

           var bankMasters = from bm in bankMasterService.GetAllBankMasters()
                             where bm.U_Bank_code.Trim().Equals(cb_bank_code.Text.Trim(), StringComparison.CurrentCultureIgnoreCase)
                             select bm;

           if (bankMasters.Any(x => x != null))
           {
               var bankMaster = bankMasters.First();

               lbl_show_bank_name.Text = bankMaster.U_Bank_name;

               CbBankCode = bankMaster.U_Bank_code;

           }
           else
           {
               //clear textfields after input
               lbl_show_bank_name.Text = string.Empty;
           }

Im new to C# and dot net and do not know how the syntax to change the statement. Any help appreciated

Answer 1

Although you should look at refactoring your data access methods to do the filtering something like this should do the trick for you

private void cb_bank_code_SelectedIndexChanged(object sender, EventArgs e)
{  
   ClearTextfieldsAfterInput();

   branchMasterBindingSource.DataSource = GetSelectedBranchMasters();

   var bankMasters = GetSelectedBankMaster();

   if (bankMasters.Any(x => x != null))
   {
       var bankMaster = bankMasters.First();

       lbl_show_bank_name.Text = bankMaster.U_Bank_name;
       CbBankCode = bankMaster.U_Bank_code;
   }
   else
   {
       //clear textfields after input
       lbl_show_bank_name.Text = string.Empty;
   }
}

private IEnumerable<BankMaster> GetSelectedBankMaster()
{
    var selectedBank = cb_bank_code.Text.Trim();
    return Program.Kernel.Get<IBankMasterService>()
        .GetAllBankMasters()
        .Where(bm => bm.U_Bank_code.Trim().Equals(selectedBank, StringComparison.CurrentCultureIgnoreCase))
        .ToList();
}

private IEnumerable<BranchMaster> GetSelectedBranchMasters()
{
    var selectedBank = cb_bank_code.Text.Trim();
    return Program.Kernel.Get<IBranchMasterService>()
        .GetAllBranchMasters()
        .Where(branch => string.Equals(branch.U_bank_code, selectedBank, StringComparison.CurrentCultureIgnoreCase))
        .ToList();
}

private void ClearTextfieldsAfterInput()
{
   lbl_show_bank_name.Text = "";
   txt_branch_code.Text = "";
   txt_branch_name.Text = "";
   txt_swift_sort_code.Text = "";
   txt_address_1.Text = "";
   txt_address_2.Text = "";
   txt_comments.Text = "";
}