Datagridview更新帮助 [英] Datagridview update help

问题描述

大家好，我正在做我的第一个winforms EDM项目，并且试图用一个可由用户更新的Presenters列表填充Datagridview.我网格中的列是名称和电子邮件地址(DataGridViewLinkColumn).到目前为止，我已经能够正确显示网格，但是当我尝试添加新行时，即使我收到一个msgbox来表示所做的更改，我的更改也不会保存回数据库.这是我填充DGV的方式:

Hi everyone, I''m working on my first winforms EDM project and I''m trying to populate a Datagridview with a list of Presenters that can be updated by a user. The cols in my grid are Name and Email address(DataGridViewLinkColumn). So far I have been able to display the grid correctly but when I try to add a new row my changes are not being saved back to the DB even though I get a msgbox to say they have. Here''s how I''m populating my DGV:

private void frmPresenters_Load(object sender, EventArgs e)
{
  dal = new DataAccessLayer();

  try
  {
    //Get the List of Contacts from the DAL and bind to the DataGrid
    source = new BindingSource();
    source.DataSource = dal.GetPresentersList();

   this.dgvPresenters.DataSource = source;
   dgvPresenters.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;
   dgvPresenters.AutoSizeRowsMode = DataGridViewAutoSizeRowsMode.AllCells;
  }
  catch (Exception ex)
  {
     MessageBox.Show(string.Format("Exception occurred: {0}", ex.Message));
  }
}

我也无法编辑电子邮件地址"字段(我认为这可能是一个单独的线程)

所有更新都是通过单击按钮进行的​​:

I''m unable to edit the Email address field as well (i think this may be a seperate thread)

all updates are made by clicking a button:

private void btnSave_Click(object sender, EventArgs e)
{
   try
   {
      // Save object changes to the database, display a message, and refresh the form.
      this.source.EndEdit();
      //dal.entities.SaveChanges();
      MessageBox.Show("Changes saved to the database.");
      this.Refresh();
   }
   catch (Exception ex)
   {
      MessageBox.Show(ex.Message);
   }
}

谁能帮我吗?

更正了第一个代码块中未正确设置的C#的[edit] pre标签-PES [/edit]

Can anyone help me please?

[edit]pre tag for C# not set properly in the first code block is corrected - PES [/edit]

推荐答案

如Wes Aday ，调用 EndEdit 从 DataGridView 实例不会将更改保存到数据库.为此，您可以使用 TableAdapter .调用其 Update 方法会将更改保存到数据库.

如何使用DataGrid插入，更新和删除 [ ^ ]

使用VS C#Windows Form中的datagridview更新SQL中的数据 [带有明细表的DataGridView-VS 2005 [ ^ ]

第4步:插入，更新和删除数据 [

As mentioned by Wes Aday, calling EndEdit from the DataGridView instance does not save changes to the database. To do that you can use a TableAdapter. Calling its Update method will save changes to the database.

How to insert, update, delete using DataGrid[^]

Updating data in SQL using datagridview in VS C# Windows Form[^]

DataGridView with Detail Edit Form - VS 2005[^]

Step 4: Inserting, Updating, and Deleting Data[^]

The above links are informative and provide examples.

不是使用List对象填充Datagridview，而是将以下内容用作Datagridview.datasource

instead of populating the Datagridview with a List object I am now using the following as my Datagridview.datasource

public ObjectResult<presenters> GetPresentersList()
{
   // Check we have an ObjectContext
   if (entities == null) entities = new CompanySecretaryEntities();
      // Create a query from the entityset
      var query = from p in entities.Presenters
	          select p;
		
      ObjectQuery<presenters> presenters = (ObjectQuery<presenters>)query;

      return presenters.Execute(MergeOption.AppendOnly);
}</presenters></presenters></presenters>

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