共用方式為


TextBox.BeforeTextChanging 事件

定義

當文字方塊中的文字開始變更,但在 Text 屬性更新之前, 就會 同步發生。

// 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"/>

事件類型

Windows 需求

裝置系列
Windows 10 Fall Creators Update (已於 10.0.16299.0 引進)
API contract
Windows.Foundation.UniversalApiContract (已於 v5.0 引進)

適用於

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