如何:从页函数返回
本示例显示如何从页函数返回结果。
示例
要从页函数返回,你需要调用 OnReturn 并传递 ReturnEventArgs<T> 的实例。
<PageFunction
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:sys="clr-namespace:System;assembly=mscorlib"
x:Class="UsingPageFunctionsSample.GetStringPageFunction"
x:TypeArguments="sys:String"
Title="GetStringPageFunction">
</PageFunction>
public partial class GetStringPageFunction : PageFunction<String>
{
public GetStringPageFunction()
{
InitializeComponent();
}
public GetStringPageFunction(string initialValue) : this()
{
this.stringTextBox.Text = initialValue;
}
void okButton_Click(object sender, RoutedEventArgs e)
{
// Page function is accepted, so return a result
OnReturn(new ReturnEventArgs<string>(this.stringTextBox.Text));
}
void cancelButton_Click(object sender, RoutedEventArgs e)
{
// Page function is cancelled, so don't return a result
OnReturn(new ReturnEventArgs<string>(null));
}
}
Partial Public Class GetStringPageFunction
Inherits PageFunction(Of String)
Public Sub New()
InitializeComponent()
End Sub
Public Sub New(ByVal initialValue As String)
Me.New()
Me.stringTextBox.Text = initialValue
End Sub
Private Sub okButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
' Page function is accepted, so return a result
OnReturn(New ReturnEventArgs(Of String)(Me.stringTextBox.Text))
End Sub
Private Sub cancelButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
' Page function is cancelled, so don't return a result
OnReturn(New ReturnEventArgs(Of String)(Nothing))
End Sub
End Class