Use of EVENT in Dynamics 365 for Operations

In legacy X++, it was possible to prescribe in metadata that certain methods were to be executed prior to and after the execution of a method. The information about what subscribes call was recorded on the publisher, which isn’t useful in the Dynamics AX environment. It’s now possible to provide Pre and Post handlers through code, by providing the SubscribesTo attribute on the subscribers.

Here is a blog showing some of basic use of EVENTS handlers of the Form with respective syntax for logics.

Form datasource from xFormRun

[FormEventHandler(formStr(SomeForm), FormEventType::Initialized)]
public static void SomeForm_OnInitialized(xFormRun sender, FormEventArgs e)
{
FormDataSource MyRandomTable_ds = sender.dataSource(formDataSourceStr(SomeForm, MyRandomTableDS));
...
}

Get FormRun from form datasource

[FormDataSourceEventHandler(formDataSourceStr(MyForm, MyRandomTableDS), FormDataSourceEventType::Written)]
public static void MyRandomTableDS_OnWritten(FormDataSource sender, FormDataSourceEventArgs e)
{
FormRun formRun = sender.formRun() as FormRun;
formRun.myCustomMethod();
}

Get FormRun from form control

[FormControlEventHandler(formControlStr(MyForm, MyButton), FormControlEventType::Clicked)]
public static void MyButton_OnClicked(FormControl sender, FormControlEventArgs e)
{
FormRun formRun = sender.formRun() as FormRun;
formRun.myCustomMethod();
}

Access form control from xFormRun

[FormEventHandler(formStr(SomeForm), FormEventType::Initialized)]
public static void SomeForm_OnInitialized(xFormRun sender, FormEventArgs e)
{
sender.design().controlName(formControlStr(SomeForm, MyControl)).visible(false);
}

Get current record in form control event

[FormControlEventHandler(formControlStr(SomeForm, SomeButton), FormControlEventType::Clicked)]
public static void SomeButton_OnClicked(FormControl sender, FormControlEventArgs e)
{
SomeTable callerRec = sender.formRun().dataSource(1).cursor();
}