PetaPoco 更新只是修改了 winform 中的记录 [英] PetaPoco update just modified records in winforms

问题描述

我有这个代码:

namespace PetaPocoTest
{
    public partial class Form1 : Form
    {
        PetaPoco.Database db = new PetaPoco.Database("PgConnection");

        IEnumerable<customers> allCustomers;


        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            allCustomers = db.Query<customers>("SELECT * FROM customers");
            mGrid.DataSource = allCustomers .ToList();            
        }

        private void saveButton_Click(object sender, EventArgs e)
        {
             foreach (var a in allCustomers)
             {
               db.Save("customers", "custumer_id", a);
             }
        }
    }
}

bat 这会更新所有记录，无论它们是否更改.所以，我的问题是有人知道如何只更新 petapoco 中更改的记录吗?

bat this updates all record, no matter if they are changed or not. So, my question is does anyone know how to update only changed records in petapoco ?

推荐答案

我就是这样做的(最终！):

This is how I did it (eventually!) :

namespace PetaPocoTest
{
    public partial class Form1 : Form
    {
        PetaPoco.Database db = new PetaPoco.Database("PgConnection");
        Dictionary<string, int> modRows = new Dictionary<string, int>();

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            bindingSource = db.Fetch<customers>("SELECT * FROM customers");
            mGrid.DataSource = bindingSource;            
        }

        private void saveButton_Click(object sender, EventArgs e)
        {
           db.BeginTransaction();

               foreach (customers c in bindingSource)
               {
                   if (modRows.ContainsKey(c.id.ToString()))
                   {
                       db.Save("customers", "id", c);
                   }
               }

           db.CompleteTransaction();
        }

        private void mGrid_CellValueChanged(object sender, DataGridViewCellEventArgs e)
        {
            int recId = ((customers)bindingSource.Current).id;

            if (!modRows.ContainsKey(recId.ToString()))
            {
               modRows.Add(recId.ToString(), recId);
            }
        }

    }
}

它的功能，但如果有人有更好的想法，请分享！

It functions, but if anyone has better idea pls share!

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