我在MS Access中有一个绑定表格。我想能够告诉：
我认为事件Form.AfterUpdate和Form.AfterInsert对此很合适，但是我刚刚测试了Form.AfterUpdate，发现它在更新和插入之后触发。
是否可以通过Form_AfterUpdate()来区分更新和插入之间的区别？还是我应该考虑使用另一种方法来检测Access中的这些事件？
Private Sub Form_AfterInsert()
Debug.Print "after insert"
End Sub
Private Sub Form_AfterUpdate()
Debug.Print "after update"
End Sub
当我插入新记录时，将打印此记录：
after update
after insert
当我更新现有记录时，将打印以下内容：
after update
答案 0 :(得分：0)
如果您真的只需要知道这是新记录承诺还是现有记录承诺，请使用$事件设置一个模块级变量，然后可以在 @override
Widget build(BuildContext context){
return new Scaffold(
appBar : LBAppBar().getAppBar(),
//drawer: new LBDrawer().getDrawer(),
body: Container(
decoration: BoxDecoration(
gradient: new LinearGradient(
colors: [Color.fromRGBO(1,89,99, 1.0), Colors.grey],
begin: Alignment.bottomLeft,
end: Alignment.topRight
)
),
child:
SwipeDetector(
onSwipeRight: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new WidgetsPage())
); },
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children:[
Row(
children: [
Container(
margin: EdgeInsets.only(left: 20.0,top: 10.0, bottom: 10.0, right:30.0),
child: Column(
children: <Widget>[
Text("Hi ${user.firstName}, Today is " + formatDate(), style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.bold, fontSize: 19.0
)),
],
),
),
]
),
Row(
//ROW 1
children: [
Container(
margin: EdgeInsets.only(left: 30.0,top: 60.0, bottom: 30.0, right:30.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.checkSquare,
size: 50.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new CheckIn()));
}),
Text("Check In", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
Container(
margin: EdgeInsets.only(left: 50.0,top: 60.0, bottom: 30.0, right:30.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.list,
size: 50.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new DayAtAGlance()));
}),
Text("My Day", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
Container(
margin: EdgeInsets.only(left: 30.0,top: 60.0, bottom: 30.0, right:30.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.phone,
size: 45.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new CommunicationLinks()));
}),
Text("Communication", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
]
),
Row(//ROW 2
children: [
Container(
margin: EdgeInsets.only(left: 32.0,top: 50.0, bottom: 30.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.dollarSign,
size: 50.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new Budget()));
}),
Text("Budget", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
Container(
margin: EdgeInsets.only(left: 75.0, top: 50.0, bottom: 30.0, right: 30.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.trophy,
size: 50.0,
color: Colors.white70,
),
onTap: () {
print("Pressed");
}),
Text("Goals", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
Container(
margin: EdgeInsets.only(left: 50.0, top: 50.0, bottom: 30.0, right: 20.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.calendar,
size: 50.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new CalendarsPage()));
}),
Text("Calendar", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
)
]),
Row(// ROW 3
children: [
Container(
margin: EdgeInsets.only(left: 30.0, top: 50.0, bottom: 30.0, right: 30.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.comments,
size: 50.0,
color: Colors.white70,
),
onTap: () {
print("Pressed");
}),
Text("Community", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
Container(
margin: EdgeInsets.only(left: 20.0, top: 50.0, bottom: 30.0, right: 20.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.shoppingCart,
size: 50.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new ShoppingList()));
}),
Text("Shopping", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.normal ))
],
),
),
Container(
margin: EdgeInsets.only(left: 50.0, top: 50.0, bottom: 30.0, right: 40.0),
child: Column(
children: <Widget>[
GestureDetector(
child: Icon(
FontAwesomeIcons.solidCheckSquare,
size: 50.0,
color: Colors.white70,
),
onTap: () {
Navigator.of(context).push(new MaterialPageRoute(builder: (BuildContext context) => new CheckOut()));
}),
Text("Check Out", style: new TextStyle( color: Colors.white70, fontWeight: FontWeight.bold ))
],
),
),
]),
],
),
)
//here
)
);
}}
事件中读取该变量。 / p>
BeforeUpdate答案 1 :(得分：0)
我认为，如果这对您很重要，那么您不应使用AfterUpdate或AfterInsert，而实际上应该使用BeforeUpdate事件。您无需说出为什么要知道记录是插入还是更新，也不必说两种情况下的计划。即便如此，我还是很难构思出一个好的场景，在这个场景中，您需要在After***事件中知道这一点。
在BeforeUpdate中，您仍然可以检查NewRecord属性并据此采取一些措施。更重要的是，您可以通过在Cancel事件中将BeforeUpdate参数设置为true来取消插入/更新的尝试。
另外，要呈现一个不同的选项-如果您希望执行的操作是以数据为中心的，并且不管数据是如何输入的，都是正确的，无论是否通过这种特殊形式，您都应该考虑使用数据宏，确实区分插入和更新。请注意，如果数据宏操作不足以执行所需的操作，您仍然可以从数据宏中调出VBA代码。
AfterUpdate和AfterInsert事件非常适合事后处理事情，通常不关心记录的产生方式。示例包括诸如刷新相关表单，更改焦点，启用/禁用控件之类的内容。请注意，我引用的示例都是与UI相关的。这就是它的用途，应该这样使用。