我正在创建一个模块，它是一个编辑帐单模块，使用户可以编辑数据库中的可用模块。我面临一个验证问题，即当用户不想编辑账单时点击“取消”按钮将返回列表视图继续选择另一条记录。这是我的问题，因为当用户没有做任何修改和＆amp;不小心点击“状态”组合从“UNPAID”到“PAID”然后直接点击。当重新选择记录时，记录状态值将变为“PAID”而不是“UNPAID”，这是实际值。
如果每次用户不进行任何修改时，我该怎么做？返回列表视图将设置组合框的默认值。
感谢大家查看此问题＆amp;希望收到回复：）
我会附上我的代码，以便轻松引用： XAML文件
<Window x:Class="HouseWivesSavior.HomecareModule.EditBillRemainder"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="EditBillRemainder" Height="600" Width="800" Loaded="Window_Loaded">
<Window.Background>
<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#FFFFFFFF" Offset="0"/>
<GradientStop Color="#FFFF00FF" Offset="1"/>
</LinearGradientBrush>
</Window.Background>
<Window.Resources>
<DataTemplate x:Key="MyDataTemplate">
<Border BorderBrush="#FF000000" BorderThickness="1,1,0,1" Margin="-6,-2,-6,-2">
<StackPanel Margin="6,2,6,2">
<TextBlock Text="{Binding Path=BillName}"/>
</StackPanel>
</Border>
</DataTemplate>
<DataTemplate x:Key="MyDataTemplate2">
<Border BorderBrush="#FF000000" BorderThickness="1,1,0,1" Margin="-6,-2,-6,-2">
<StackPanel Margin="6,2,6,2">
<TextBlock Text="{Binding Path=BillDescription}"/>
</StackPanel>
</Border>
</DataTemplate>
<DataTemplate x:Key="MyDataTemplate3">
<Border BorderBrush="#FF000000" BorderThickness="1,1,0,1" Margin="-6,-2,-6,-2">
<StackPanel Margin="6,2,6,2">
<TextBlock Text="{Binding Path=BillAmount}"/>
</StackPanel>
</Border>
</DataTemplate>
<DataTemplate x:Key="MyDataTemplate4">
<Border BorderBrush="#FF000000" BorderThickness="1,1,1,1" Margin="-6,-2,-6,-2">
<StackPanel Margin="6,2,6,2">
<TextBlock Text="{Binding Path=BillDueDate, StringFormat='dd-MM-yyyy'}"/>
</StackPanel>
</Border>
</DataTemplate>
<Style x:Key="MyItemContainerStyle" TargetType="{x:Type ListViewItem}">
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
<Setter Property="VerticalContentAlignment" Value="Stretch" />
<!--<EventSetter Event="PreviewMouseLeftButtonDown" Handler="ListViewItem_PreviewMouseLeftButtonDown" />-->
</Style>
<!--DatePickerTextBoxFormat-->
<Style TargetType="{x:Type DatePickerTextBox}">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<TextBox x:Name="PART_TextBox" Text="{Binding Path=SelectedDate, StringFormat='dd-MM-yyyy', RelativeSource={RelativeSource AncestorType={x:Type DatePicker}}}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<ListView Name="lvwBooks" Background="White" ItemsSource="{Binding}" Margin="131,130,4,6" ItemContainerStyle="{DynamicResource MyItemContainerStyle}">
<ListView.View>
<GridView>
<GridViewColumn Header="Bill Name" Width="100" CellTemplate="{DynamicResource MyDataTemplate}"/>
<GridViewColumn Header="Description" Width="250" CellTemplate="{DynamicResource MyDataTemplate2}"/>
<GridViewColumn Header="Amount" Width="160" CellTemplate="{DynamicResource MyDataTemplate3}"/>
<GridViewColumn Header="Due Date" Width="100" CellTemplate="{DynamicResource MyDataTemplate4}"/>
<GridViewColumn Header="Edit">
<GridViewColumn.CellTemplate>
<DataTemplate>
<UserControl>
<Hyperlink Click="InputBox_Click">Edit
<Hyperlink.Style>
<Style TargetType="{x:Type Hyperlink}">
<Setter Property="Hyperlink.IsEnabled" Value="False" />
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource AncestorType={x:Type ListViewItem}}, Path=IsSelected}" Value="True">
<Setter Property="Hyperlink.IsEnabled" Value="True" />
</DataTrigger>
</Style.Triggers>
</Style>
</Hyperlink.Style>
</Hyperlink>
</UserControl>
</DataTemplate>
</GridViewColumn.CellTemplate>
</GridViewColumn>
</GridView>
</ListView.View>
</ListView>
<!-- It's important that this is in the end of the XAML as it needs to be on top of everything else! -->
<Grid x:Name="InputBox" Visibility="Collapsed">
<Grid Background="Black" Opacity="0.5" />
<Border
MinWidth="250"
Background="Orange"
BorderBrush="Black"
BorderThickness="1"
CornerRadius="0,40,0,40"
HorizontalAlignment="Center"
VerticalAlignment="Center" Height="493" Margin="130,30,120,38" Width="528">
<Canvas Height="446" Width="524">
<GroupBox Header="General Information" Height="141" HorizontalAlignment="Left" Margin="193,52,0,0" Name="groupBox1" VerticalAlignment="Top" Width="495" Canvas.Left="-173" Canvas.Top="-67">
<Canvas Background="WhiteSmoke" Opacity="1">
<GridSplitter Background="#FFBCBCBC" HorizontalAlignment="Left" Margin="207,13,0,140" ResizeBehavior="PreviousAndNext" Width="2" Height="50" Canvas.Left="-3" Canvas.Top="48" />
<TextBlock Height="23" HorizontalAlignment="Left" Margin="6,6,0,0" Name="textBlock1" Text="Bill Name" VerticalAlignment="Top" />
<TextBlock Height="23" HorizontalAlignment="Left" Margin="215,65,0,0" Name="textBlock4" Text="Due Date" VerticalAlignment="Top" Grid.ColumnSpan="2" />
<GridSplitter HorizontalAlignment="Left" ResizeBehavior="PreviousAndNext"
Width="1" Background="#FFBCBCBC" Margin="206,63,0,9" />
<DatePicker Height="25" HorizontalAlignment="Right" Margin="0,80,157,0" Name="BillDueDatedatePicker" VerticalAlignment="Top" Width="115" Grid.ColumnSpan="2" Canvas.Left="215" Canvas.Top="6" Text="{Binding Path=BillDueDate, StringFormat='dd-MM-yyyy'}" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}" SelectedDateFormat="Short"/>
<TextBox Height="23" HorizontalAlignment="Left" Margin="7,29,0,0" Name="BillNameTxtBox" VerticalAlignment="Top" Width="458" Grid.ColumnSpan="2" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}" Text="{Binding Path=BillName}"/>
<TextBlock Height="23" HorizontalAlignment="Left" Margin="7,63,0,0" Name="textBlock8" Text="Bill Type" VerticalAlignment="Top" />
<ComboBox Height="23" HorizontalAlignment="Left" Margin="8,81,0,0" Name="BillTypeCboBox" VerticalAlignment="Top" Width="193" Canvas.Left="-5" Canvas.Top="8" Text="{Binding Path=BillTypes}" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}">
<ComboBoxItem Content="Water" />
<ComboBoxItem Content="Electricity" />
<ComboBoxItem Content="Gas" />
<ComboBoxItem Content="Internet/broadband"/>
<ComboBoxItem Content="Others"/>
</ComboBox>
<TextBox Canvas.Left="62" Canvas.Top="3" Height="23" Name="textBox1" Width="120" Visibility="Visible" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}" Text="{Binding Path=BillNo}"/>
</Canvas>
</GroupBox>
<GroupBox Header="Payment Information" Height="339" HorizontalAlignment="Left" Margin="193,202,0,0" Name="groupBox2" VerticalAlignment="Top" Width="495" Canvas.Left="-174" Canvas.Top="-81">
<Canvas Background="WhiteSmoke" Height="303" Visibility="Visible">
<TextBlock Height="23" HorizontalAlignment="Left" Margin="7,17,0,0" Name="textBlock6" Text="Amount Due" VerticalAlignment="Top" />
<TextBlock Height="23" HorizontalAlignment="Left" Margin="7,75,0,0" Name="textBlock7" Text="Description" VerticalAlignment="Top" />
<TextBox Height="23" HorizontalAlignment="Left" Margin="81,14,0,0" Name="BillAmountTxtBox" VerticalAlignment="Top" Width="120" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}" Text="{Binding Path=BillAmount}"/>
<TextBox Height="148" HorizontalAlignment="Left" Margin="4,96,0,0" Name="BillDescriptionTxtBox" VerticalAlignment="Top" Width="471" VerticalScrollBarVisibility="Visible" SpellCheck.IsEnabled="True" TextWrapping="Wrap" AcceptsReturn="True" Text="{Binding Path=BillDescription}" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}"/>
<TextBlock Height="23" HorizontalAlignment="Left" Margin="6,46,0,0" Name="textBlock9" Text="Status" VerticalAlignment="Top" />
<ComboBox Height="23" HorizontalAlignment="Left" Margin="81,46,0,0" Name="BillStatusCboBox" VerticalAlignment="Top" Width="120" SelectionChanged="comboBox3_SelectionChanged" Text="{Binding Path=BillStatus}" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}" >
<ComboBoxItem Content="UNPAID" />
<ComboBoxItem Content="PAID" />
</ComboBox>
<TextBlock Height="23" HorizontalAlignment="Left" Margin="215,14,0,0" Name="textBlock10" Text="Bill is Paid:" VerticalAlignment="Top" />
<DatePicker Text="{Binding Path=BillPaidDate}" Height="25" HorizontalAlignment="Left" Margin="212,37,0,0" Name="BillPaidDatedatePicker" VerticalAlignment="Top" Width="115" IsEnabled="false" DataContext="{Binding ElementName=lvwBooks, Path=SelectedItem}"/>
<GridSplitter Background="#FFBCBCBC" HorizontalAlignment="Left" Margin="205,14,0,228" ResizeBehavior="PreviousAndNext" Width="2" />
<Separator Height="26" HorizontalAlignment="Left" Margin="7,250,0,0" Name="separator1" VerticalAlignment="Top" Width="470" />
<Button Content="Done" Height="23" HorizontalAlignment="Left" Margin="322,267,0,0" Name="button1" VerticalAlignment="Top" Width="75" Click="YesButton_Click" />
<Button Content="Cancel" Height="23" HorizontalAlignment="Left" Margin="402,266,0,0" Name="button2" VerticalAlignment="Top" Width="75" Click="NoButton_Click" />
<GridSplitter Background="#FFBCBCBC" HorizontalAlignment="Left" Margin="207,13,0,140" ResizeBehavior="PreviousAndNext" Width="0" />
</Canvas>
</GroupBox>
</Canvas>
</Border>
</Grid>
</Grid>
</Window>
代码背后：
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.Data.SqlClient;
using System.Configuration;
using System.Data;
namespace HouseWivesSavior.HomecareModule
{
/// <summary>
/// Interaction logic for EditBillRemainder.xaml
/// </summary>
public partial class EditBillRemainder : Window
{
public EditBillRemainder()
{
InitializeComponent();
}
private void Window_Loaded(object sender, RoutedEventArgs e)
{
ShowData();
}
private void InputBox_Click(object sender, RoutedEventArgs e)
{
// CoolButton Clicked! Let's show our InputBox.
InputBox.Visibility = System.Windows.Visibility.Visible;
}
private void NoButton_Click(object sender, RoutedEventArgs e)
{
//ShowData();
// NoButton Clicked! Let's hide our InputBox.
InputBox.Visibility = System.Windows.Visibility.Collapsed;
}
private void ListViewItem_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
var item = sender as ListViewItem;
if (item != null && item.IsSelected)
{
}
}
//Design
private void comboBox3_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
////The logic for this will be stanger but in order to cope iwht the SelectionChange behavior.
//string s1 = BillStatusCboBox.SelectionBoxItem.ToString();
//// MessageBox.Show(s1);
//if (s1.Equals("UNPAID"))
//{
// BillPaidDatedatePicker.IsEnabled = true;
// BillPaidDatedatePicker.Text = DateTime.Now.ToString("d/MM/yyyy");
//}
//if (s1.Equals("PAID"))
//{
// BillPaidDatedatePicker.IsEnabled = false;
// //BillStatusCboBox.SelectedIndex = 0;
//}
ComboBoxItem currentItem = ((System.Windows.Controls.ComboBoxItem)BillStatusCboBox.SelectedItem);
if (currentItem.Content.Equals("PAID"))
{
BillPaidDatedatePicker.IsEnabled = true;
// BuilderupdateButton.Visibility = Visibility.Visible;
}
else {
BillPaidDatedatePicker.IsEnabled = false;
}
}
//Database
public void ShowData()
{
SqlConnection conn;
string connStr = ConfigurationManager.ConnectionStrings["house"].ConnectionString;
conn = new SqlConnection(connStr);
//SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True");
conn.Open();
SqlCommand comm = new SqlCommand("Select * from bill ORDER BY BillDueDate", conn);
DataTable dt = new DataTable();
SqlDataAdapter da = new SqlDataAdapter(comm);
da.Fill(dt);
lvwBooks.DataContext = dt.DefaultView;
}
private void YesButton_Click(object sender, RoutedEventArgs e)
{
Update();
// YesButton Clicked! Let's hide our InputBox and handle the input text.
InputBox.Visibility = System.Windows.Visibility.Collapsed;
}
public void Update() {
SqlConnection conn;
SqlCommand cmdInsert;
String strUpdate;
string connStr = ConfigurationManager.ConnectionStrings["house"].ConnectionString;
conn = new SqlConnection(connStr);
strUpdate = "UPDATE bill SET BillName=@BillName, BillTypes=@BillTypes, BillDueDate=@BillDueDate, BillAmount=@BillAmount, BillStatus=@BillStatus, BillPaidDate=@BillPaidDate, BillDescription=@BillDescription WHERE BillNo='" + textBox1.Text + "' ";
cmdInsert = new SqlCommand(strUpdate, conn);
cmdInsert.Parameters.AddWithValue("@BillName", BillNameTxtBox.Text);
cmdInsert.Parameters.AddWithValue("@BillTypes", BillTypeCboBox.Text);
cmdInsert.Parameters.AddWithValue("@BillDueDate", DateTime.Parse(BillDueDatedatePicker.Text));
cmdInsert.Parameters.AddWithValue("@BillAmount", BillAmountTxtBox.Text);
cmdInsert.Parameters.AddWithValue("@BillStatus", BillStatusCboBox.Text);
//MessageBox.Show(BillPaidDatedatePicker.Text);
if (BillPaidDatedatePicker.Text.Equals(""))
{
cmdInsert.Parameters.AddWithValue("@BillPaidDate", "");
}
else {
cmdInsert.Parameters.AddWithValue("@BillPaidDate", DateTime.Parse(BillPaidDatedatePicker.Text));
}
// cmdInsert.Parameters.AddWithValue("@BillPaidDate", DateTime.Parse(empty));
cmdInsert.Parameters.AddWithValue("@BillDescription", BillDescriptionTxtBox.Text);
try
{
conn.Open();
int result = cmdInsert.ExecuteNonQuery();
if (result == 1)
{
MessageBox.Show("Bill Edited!!!");
}
}
catch (SqlException ex)
{
MessageBox.Show(ex.ToString());
}
finally {
conn.Close();
}
}
}
}
答案 0 :(得分：0)
对于这种情况，最好使用IDataErrorInfo接口而不是使用ValiationRule，因为IDataErrorInfo将在ViewModel中处理，在那里您还拥有所有必要的数据库语句。
这是一个教程的链接，解释了如何使用IDataErrorInfo进行验证。
http://codeblitz.wordpress.com/2009/05/08/wpf-validation-made-easy-with-idataerrorinfo/
玩得开心：）
答案 1 :(得分：0)
我这样解决了： 代码隐藏： 我遇到的问题是NullReferenceException然后我用try..catch来捕获“NullReferenceException”
private void comboBox3_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ComboBoxItem currentItem = ((System.Windows.Controls.ComboBoxItem)BillStatusCboBox.SelectedItem);
try
{
if (currentItem.Content.Equals("PAID"))
{
BillPaidDatedatePicker.IsEnabled = true;
// BuilderupdateButton.Visibility = Visibility.Visible;
}
else
{
BillPaidDatedatePicker.IsEnabled = false;
}
}
catch (NullReferenceException ex){ // At here which you can see.
//I purposely set it to do nothing when catch it.
}
然后当用户意外点击“UPAID”到“PAID”＆amp;直接点击取消按钮将调用“NoButton_Click”，这将尝试重新加载＆amp;从数据库中选择值：
private void NoButton_Click(object sender, RoutedEventArgs e)
{
ShowData(); // Invoke & select from database again.
// NoButton Clicked! Let's hide our InputBox.
InputBox.Visibility = System.Windows.Visibility.Collapsed;
}
我知道通过这种方式解决我的问题将会非常低效但是完成工作:)这对我来说很好。