[英]Cancel button writes to text box
我有一个wpf应用程序,提示用户从主窗口输入一些数字输入,以设置秒数来设置失效时间。 该值的默认值为120,如果用户希望对其进行更改,则可以单击该按钮,然后将出现一个新的窗口实例,并提示用户对其进行更改,我可以使用数字验证部分,但是如果用户单击“取消”按钮,当前值将被空白(“”)空格替代,因为从技术上讲,这是输入时间窗口文本框中的值。 我将如何阻止这种情况的发生? 我只希望窗口关闭当前值以保持原样。 注意如果用户在框中输入“ 3”,即使用户单击“取消”,默认值也将替换为3,也会发生这种情况。
这是WPF:
<Window x:Class="WpfClient.StaleTimeDialog"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Stale Time" FontFamily="Arial" Width="450" Height="300" Topmost="True" WindowStartupLocation="CenterScreen" ResizeMode="NoResize">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"></RowDefinition>
<RowDefinition Height="Auto"></RowDefinition>
<RowDefinition Height="Auto"></RowDefinition>
<RowDefinition Height="*"></RowDefinition>
</Grid.RowDefinitions>
<Label Margin="10" FontSize="16">Enter new Stale Time</Label>
<StackPanel Grid.Row="1" Orientation="Horizontal" HorizontalAlignment="Center" Margin="0, 10, 10, 0">
<TextBox Name="StaleTime" FontSize="20" Width="150" HorizontalAlignment="Left" VerticalContentAlignment="Center" Text="" AcceptsReturn="False" DataContext="{Binding}" PreviewTextInput="StaleTime_PreviewTextInput"></TextBox>
<Label Width="Auto" FontSize="20" Height="Auto" VerticalContentAlignment="Center">Seconds</Label>
</StackPanel>
<StackPanel Grid.Row="3" HorizontalAlignment="Right" VerticalAlignment="Bottom" Orientation="Horizontal">
<Button Name="SaveButton" Margin="10,10,10,10" Style="{StaticResource controlButtonStyle}" IsDefault="True" Click="SaveButton_Click">Save</Button>
<Button Name="CancelButton" Margin="10,10,10,10" Style="{StaticResource controlButtonStyle}" IsCancel="True" Click="CancelButton_Click">Cancel</Button>
</StackPanel>
</Grid>
这是C#:
public partial class StaleTimeDialog : Window
{
private Client client = null;
private SystemStatus systemStatus = null;
private UserTypes userType = UserTypes.Unknown;
private bool isStandaloneGUI = false;
private static string CurrentValue = "";
public StaleTimeDialog()
{
InitializeComponent();
CurrentValue = StaleTime.Text;
}
private void Cancel_Click(object sender, EventArgs e)
{
StaleTime.Text = CurrentValue.ToString();
CancelButton.IsCancel = true;
this.Close();
}
private void StaleTime_KeyPress(object sender, KeyEventArgs e)
{
if (e.Key == Key.Enter)
{
e.Handled = true;
}
}
private void SaveButton_Click(object sender, RoutedEventArgs e)
{
if (true)
{
this.Close();
}
else
{
ErrorDialog errorDialog = new ErrorDialog(DialogType.OKDialog, IconType.Warning, "Save failed");
errorDialog.ShowDialog();
}
}
private void StaleTime_PreviewTextInput(object sender, TextCompositionEventArgs e)
{
CheckIsNumeric(e);
}
private void CheckIsNumeric(TextCompositionEventArgs e)
{
int result;
if (!(int.TryParse(e.Text, out result) || e.Text == "."))
{
e.Handled = true;
}
}
private void CancelButton_Click(object sender, RoutedEventArgs e)
{
this.DialogResult = false;
StaleTime.Undo();
}
}
这是在C#中调用它的实例:
private void EditParametersButton_Click(object sender, RoutedEventArgs e)
{
StaleTimeDialog staletimeDialog = new StaleTimeDialog();
bool? result = staletimeDialog.ShowDialog();
if (staletimeDialog.StaleTime.Text.Equals("") || staletimeDialog.StaleTime.Text.Equals(" "))
{
App.ChipStale = DefaultStaleTime;
}
else
{
App.ChipStale = Convert.ToInt32(staletimeDialog.StaleTime.Text);
}
FoodParametersLine4Run.Text = App.ChipStale.ToString();
}
您需要将TwoWay
模式下的TextBox
Text
属性绑定到支持该视图的DataContext
的更改通知的公共属性(通常是ViewModel),并将UpdateSourceTrigger
设置为LostFocus
或Explicit
。
一旦这样做,您所有的问题都将消失,此外,您还将摆脱所有丑陋的代码……这就是WPF的工作方式。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.