TextBox.BeforeTextChanging Evento

Definizione

Spazio dei nomi:

Windows.UI.Xaml.Controls

Si verifica in modo sincrono quando il testo nella casella di testo inizia a cambiare, ma prima dell'aggiornamento della proprietà Text .

// Register
event_token BeforeTextChanging(TypedEventHandler<TextBox, TextBoxBeforeTextChangingEventArgs const&> const& handler) const;

// Revoke with event_token
void BeforeTextChanging(event_token const* cookie) const;

// Revoke with event_revoker
TextBox::BeforeTextChanging_revoker BeforeTextChanging(auto_revoke_t, TypedEventHandler<TextBox, TextBoxBeforeTextChangingEventArgs const&> const& handler) const;

public event TypedEventHandler<TextBox,TextBoxBeforeTextChangingEventArgs> BeforeTextChanging;

function onBeforeTextChanging(eventArgs) { /* Your code */ }
textBox.addEventListener("beforetextchanging", onBeforeTextChanging);
textBox.removeEventListener("beforetextchanging", onBeforeTextChanging);
- or -
textBox.onbeforetextchanging = onBeforeTextChanging;

Public Custom Event BeforeTextChanging As TypedEventHandler(Of TextBox, TextBoxBeforeTextChangingEventArgs) 

<TextBox BeforeTextChanging="eventhandler"/>

Tipo evento

TypedEventHandler<TextBox,TextBoxBeforeTextChangingEventArgs>

Requisiti Windows

Famiglia di dispositivi	Windows 10 Fall Creators Update (è stato introdotto in 10.0.16299.0)
API contract	Windows.Foundation.UniversalApiContract (è stato introdotto in v5.0)

Vedi anche

• TextBoxBeforeTextChangingEventArgs