WPF如何自定義實(shí)現IP地址輸入控件

這篇文章將為大家詳細講解有關(guān)WPF如何自定義實(shí)現IP地址輸入控件，小編覺(jué)得挺實(shí)用的，因此分享給大家做個(gè)參考，希望大家閱讀完這篇文章后可以有所收獲。

一、前言

WPF沒(méi)有內置IP地址輸入控件，因此我們需要通過(guò)自己定義實(shí)現。

我們先看一下IP地址輸入控件有什么特性：

輸滿(mǎn)三個(gè)數字焦點(diǎn)會(huì )往右移  鍵盤(pán)←→可以空光標移動(dòng)  任意位置可復制整段IP地址，且支持x.x.x.x格式的粘貼賦值  刪除字符會(huì )自動(dòng)向左移動(dòng)焦點(diǎn)

知道以上特性，我們就可以開(kāi)始動(dòng)手了。

二、構成

Grid+TextBox*4+TextBlock*3

通過(guò)這幾個(gè)控件的組合，我們完成IP地址輸入控件的功能。

界面代碼如下：

<UserControl x:Class="IpAddressControl.IpAddressControl" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:local="clr-namespace:IpAddressControl" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" Margin="10,0" d:DesignHeight="50" d:DesignWidth="800" mc:Ignorable="d" Background="White"> <UserControl.Resources>  <ControlTemplate x:Key="validationTemplate">   <DockPanel>    <TextBlock     Margin="1,2"     DockPanel.Dock="Right"     FontSize="{DynamicResource ResourceKey=Heading4}"     FontWeight="Bold"     Foreground="Red"     Text="" />    <AdornedElementPlaceholder />   </DockPanel>  </ControlTemplate>  <Style x:Key="CustomTextBoxTextStyle" TargetType="TextBox">   <Setter Property="MaxLength" Value="3" />   <Setter Property="HorizontalAlignment" Value="Stretch" />   <Setter Property="VerticalAlignment" Value="Center" />   <Style.Triggers>    <Trigger Property="Validation.HasError" Value="True">     <Trigger.Setters>      <Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self}, Path=(Validation.Errors)[0].ErrorContent}" />      <Setter Property="BorderBrush" Value="Red" />      <Setter Property="Background" Value="Red" />     </Trigger.Setters>    </Trigger>   </Style.Triggers>  </Style> </UserControl.Resources> <Grid>  <Grid.ColumnDefinitions>   <ColumnDefinition MinWidth="30" />   <ColumnDefinition Width="10" />   <ColumnDefinition MinWidth="30" />   <ColumnDefinition Width="10" />   <ColumnDefinition MinWidth="30" />   <ColumnDefinition Width="10" />   <ColumnDefinition MinWidth="30" />  </Grid.ColumnDefinitions>  <!-- Part 1 -->  <TextBox   Grid.Column="0"   BorderThickness="0"   HorizontalAlignment="Stretch"   VerticalAlignment="Stretch"   VerticalContentAlignment="Center"   HorizontalContentAlignment="Center"   x:Name="part1"   PreviewKeyDown="Part1_PreviewKeyDown"   local:FocusChangeExtension.IsFocused="{Binding IsPart1Focused, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged, NotifyOnSourceUpdated=True}"   Style="{StaticResource CustomTextBoxTextStyle}"   Validation.ErrorTemplate="{StaticResource validationTemplate}">   <TextBox.Text>    <Binding Path="Part1" UpdateSourceTrigger="PropertyChanged">     <Binding.ValidationRules>      <local:IPRangeValidationRule Max="255" Min="0" />     </Binding.ValidationRules>    </Binding>   </TextBox.Text>  </TextBox>  <TextBlock   Grid.Column="1"   HorizontalAlignment="Center"   FontSize="15"   Text="."   VerticalAlignment="Center"  />  <!-- Part 2 -->  <TextBox   Grid.Column="2"   x:Name="part2"   BorderThickness="0"   VerticalAlignment="Stretch"   VerticalContentAlignment="Center"   HorizontalContentAlignment="Center"   PreviewKeyDown="Part2_KeyDown"   local:FocusChangeExtension.IsFocused="{Binding IsPart2Focused}"   Style="{StaticResource CustomTextBoxTextStyle}"   Validation.ErrorTemplate="{StaticResource validationTemplate}">   <TextBox.Text>    <Binding Path="Part2" UpdateSourceTrigger="PropertyChanged">     <Binding.ValidationRules>      <local:IPRangeValidationRule Max="255" Min="0" />     </Binding.ValidationRules>    </Binding>   </TextBox.Text>  </TextBox>  <TextBlock   Grid.Column="3"   HorizontalAlignment="Center"   FontSize="15"   Text="."   VerticalAlignment="Center"/>  <!-- Part 3 -->  <TextBox   Grid.Column="4"   x:Name="part3"   BorderThickness="0"   VerticalAlignment="Stretch"   VerticalContentAlignment="Center"   HorizontalContentAlignment="Center"   PreviewKeyDown="Part3_KeyDown"   local:FocusChangeExtension.IsFocused="{Binding IsPart3Focused}"   Style="{StaticResource CustomTextBoxTextStyle}"   Validation.ErrorTemplate="{StaticResource validationTemplate}">   <TextBox.Text>    <Binding Path="Part3" UpdateSourceTrigger="PropertyChanged">     <Binding.ValidationRules>      <local:IPRangeValidationRule Max="255" Min="0" />     </Binding.ValidationRules>    </Binding>   </TextBox.Text>  </TextBox>  <TextBlock   Grid.Column="5"   HorizontalAlignment="Center"   FontSize="15"   Text="."   VerticalAlignment="Center"/>  <!-- Part 4 -->  <TextBox   Grid.Column="6"   x:Name="part4"   BorderThickness="0"   VerticalAlignment="Stretch"   VerticalContentAlignment="Center"   HorizontalContentAlignment="Center"   PreviewKeyDown="Part4_KeyDown"   local:FocusChangeExtension.IsFocused="{Binding IsPart4Focused}"   Style="{StaticResource CustomTextBoxTextStyle}"   Validation.ErrorTemplate="{StaticResource validationTemplate}">   <TextBox.Text>    <Binding Path="Part4" UpdateSourceTrigger="PropertyChanged">     <Binding.ValidationRules>      <local:IPRangeValidationRule Max="255" Min="0" />     </Binding.ValidationRules>    </Binding>   </TextBox.Text>  </TextBox> </Grid></UserControl>

三、驗證輸入格式

界面中為T(mén)extBox添加了CustomTextBoxTextStyle及validationTemplate樣式，當輸入格式不正確時(shí)，控件就會(huì )應用該樣式。

通過(guò)自定義規則IPRangeValidationRule來(lái)驗證輸入的內容格式是否要求。

自定義規則代碼如下：

public class IPRangeValidationRule : ValidationRule{ private int _min; private int _max; public int Min {  get { return _min; }  set { _min = value; } } public int Max {  get { return _max; }  set { _max = value; } } public override ValidationResult Validate(object value, CultureInfo cultureInfo) {  int val = 0;  var strVal = (string)value;  try  {   if (strVal.Length > 0)   {    if (strVal.EndsWith("."))    {     return CheckRanges(strVal.Replace(".", ""));    }    // Allow dot character to move to next box    return CheckRanges(strVal);   }  }  catch (Exception e)  {   return new ValidationResult(false, "Illegal characters or " + e.Message);  }  if ((val < Min) || (val > Max))  {   return new ValidationResult(false,    "Please enter the value in the range: " + Min + " - " + Max + ".");  }  else  {   return ValidationResult.ValidResult;  } } private ValidationResult CheckRanges(string strVal) {  if (int.TryParse(strVal, out var res))  {   if ((res < Min) || (res > Max))   {    return new ValidationResult(false,     "Please enter the value in the range: " + Min + " - " + Max + ".");   }   else   {    return ValidationResult.ValidResult;   }  }  else  {   return new ValidationResult(false, "Illegal characters entered");  } }}

四、控制焦點(diǎn)變化

在界面代碼中我通過(guò)local:FocusChangeExtension.IsFocused附加屬性實(shí)現綁定屬性控制焦點(diǎn)的變化。

附加屬性的代碼如下：

public static class FocusChangeExtension{ public static bool GetIsFocused(DependencyObject obj) {  return (bool)obj.GetValue(IsFocusedProperty); } public static void SetIsFocused(DependencyObject obj, bool value) {  obj.SetValue(IsFocusedProperty, value); } public static readonly DependencyProperty IsFocusedProperty =  DependencyProperty.RegisterAttached(   "IsFocused", typeof(bool), typeof(FocusChangeExtension),   new UIPropertyMetadata(false, OnIsFocusedPropertyChanged)); private static void OnIsFocusedPropertyChanged(  DependencyObject d,  DependencyPropertyChangedEventArgs e) {  var control = (UIElement)d;  if ((bool)e.NewValue)  {   control.Focus();  } }}

五、VM+后臺代碼混合實(shí)現焦點(diǎn)控制及內容復制粘貼

1、后臺代碼主要實(shí)現復制粘貼內容，另外←→移動(dòng)光標也需要后臺代碼控制。通過(guò)PreviewKeyDown事件捕獲鍵盤(pán)左移右移，復制，刪除等事件，做出相應處理：

private void Part2_KeyDown(object sender, System.Windows.Input.KeyEventArgs e){ if (e.Key == Key.Back && part2.Text == "") {  part1.Focus(); } if (e.Key == Key.Right && part2.CaretIndex == part2.Text.Length) {  part3.Focus();  e.Handled = true; } if (e.Key == Key.Left && part2.CaretIndex == 0) {  part1.Focus();  e.Handled = true; } if (e.KeyboardDevice.Modifiers.HasFlag(ModifierKeys.Control) && e.Key == Key.C) {  if (part2.SelectionLength == 0)  {   var vm = this.DataContext as IpAddressViewModel;   Clipboard.SetText(vm.AddressText);  } }}

通過(guò)DataObject.AddPastingHandler(part1, TextBox_Pasting)添加粘貼事件。使控件賦值。

2、通過(guò)ViewModel方式實(shí)現屬性綁定通知，來(lái)控制焦點(diǎn)變化及內容賦值。

ViewModel類(lèi)要實(shí)現綁定通知需要實(shí)現INotifyPropertyChanged接口中的方法。

我們新建一個(gè)IpAddressViewModel類(lèi)繼承INotifyPropertyChanged，代碼如下：

public class IpAddressViewModel : INotifyPropertyChanged{ public event EventHandler AddressChanged; public string AddressText {  get { return $"{Part1??"0"}.{Part2??"0"}.{Part3??"0"}.{Part4??"0"}"; } } private bool isPart1Focused; public bool IsPart1Focused {  get { return isPart1Focused; }  set { isPart1Focused = value; OnPropertyChanged(); } } private string part1; public string Part1 {  get { return part1; }  set  {   part1 = value;   SetFocus(true, false, false, false);   var moveNext = CanMoveNext(ref part1);   OnPropertyChanged();   OnPropertyChanged(nameof(AddressText));   AddressChanged?.Invoke(this, EventArgs.Empty);   if (moveNext)   {    SetFocus(false, true, false, false);   }  } }  private bool isPart2Focused; public bool IsPart2Focused {  get { return isPart2Focused; }  set { isPart2Focused = value; OnPropertyChanged(); } } private string part2; public string Part2 {  get { return part2; }  set  {   part2 = value;   SetFocus(false, true, false, false);   var moveNext = CanMoveNext(ref part2);   OnPropertyChanged();   OnPropertyChanged(nameof(AddressText));   AddressChanged?.Invoke(this, EventArgs.Empty);   if (moveNext)   {    SetFocus(false, false, true, false);   }  } } private bool isPart3Focused; public bool IsPart3Focused {  get { return isPart3Focused; }  set { isPart3Focused = value; OnPropertyChanged(); } } private string part3; public string Part3 {  get { return part3; }  set  {   part3 = value;   SetFocus(false, false, true, false);   var moveNext = CanMoveNext(ref part3);   OnPropertyChanged();   OnPropertyChanged(nameof(AddressText));   AddressChanged?.Invoke(this, EventArgs.Empty);   if (moveNext)   {    SetFocus(false, false, false, true);   }  } } private bool isPart4Focused; public bool IsPart4Focused {  get { return isPart4Focused; }  set { isPart4Focused = value; OnPropertyChanged(); } } private string part4; public string Part4 {  get { return part4; }  set  {   part4 = value;   SetFocus(false, false, false, true);   var moveNext = CanMoveNext(ref part4);   OnPropertyChanged();   OnPropertyChanged(nameof(AddressText));   AddressChanged?.Invoke(this, EventArgs.Empty);  } }  public void SetAddress(string address) {  if (string.IsNullOrWhiteSpace(address))   return;  var parts = address.Split('.');     if (int.TryParse(parts[0], out var num0))  {   Part1 = num0.ToString();  }  if (int.TryParse(parts[1], out var num1))  {   Part2 = parts[1];  }  if (int.TryParse(parts[2], out var num2))  {   Part3 = parts[2];  }  if (int.TryParse(parts[3], out var num3))  {   Part4 = parts[3];  } } private bool CanMoveNext(ref string part) {  bool moveNext = false;  if (!string.IsNullOrWhiteSpace(part))  {   if (part.Length >= 3)   {    moveNext = true;   }   if (part.EndsWith("."))   {    moveNext = true;    part = part.Replace(".", "");   }  }  return moveNext; } private void SetFocus(bool part1, bool part2, bool part3, bool part4) {  IsPart1Focused = part1;  IsPart2Focused = part2;  IsPart3Focused = part3;  IsPart4Focused = part4; } public event PropertyChangedEventHandler PropertyChanged; protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null) {  PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName)); }}

到這里基本就完成了，生成控件然后到MainWindow中引用該控件