.NET DataSet.HasChanges is incorrectly false

问题:

Has anybody come across ds.hasChanges() being false despite that the ds clearly has the changes while you check it at a breakpoint? I've been looking at it for quite a while and I can't see what is wrong...

// connectionstring and command has been set
DataSet ds = new DataSet();
BindingSource myBindingSource = new BindingSource();
SqlDataAdapter dataAdapter1 = new SqlDataAdapter();
dataAdapter1.Fill(ds, "Data");
myBindingSource.DataSource = ds.Tables["Data"];

// then changes made to the datatable on a windows form using bindingnavigator
ds.HasChanges(DataRowState.Modified); // is false

Now when I set a breakpoint after the row with HasChanges and use DataSet Visualizer I can see that the DataSet has in fact changed, but HasChanges still returns false.

I'm sure I'm missing the obvious... can anybody see what I'm doing wrong?

Cheers

回答1:

Try calling the EndCurrentEdit() on BindingContext first:

DataTable dt = ds.Tables["Data"];
this.BindingContext[dt].EndCurrentEdit();

if(ds.HasChanges(DataRowState.Modified))
{
  // do your stuff here
}

Also try calling the myBindingSource.EndEdit() that will push any un-commited data to the DataTable.

回答2:

The Windows Form isn't doing a .AcceptChanges() call on the DataSet is it?

Edit: Ok so not that. Next things, per my comment:
1) have records def been modified and not just added/deleted? What does DataSet.HasChanges() return?
2) what does GetChanges() return for the specific datable within the dataset?