通过

TextBox.BeforeTextChanging 事件

  • 参考

定义

命名空间:
Windows.UI.Xaml.Controls
编辑

当文本框中的文本开始更改，但在 Text 属性更新之前同步发生。

// 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"/>

事件类型

TypedEventHandler<TextBox,TextBoxBeforeTextChangingEventArgs>

Windows 要求

设备系列
Windows 10 Fall Creators Update (在 10.0.16299.0 中引入)
API contract
Windows.Foundation.UniversalApiContract (在 v5.0 中引入)

适用于

另请参阅