WPF 自定义TextBox(WPF带图片，占位符，清除按钮的TextBox)改造版

原文：https://blog.csdn.net/oneonce/article/details/77072894

效果：

Style:

    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:ctrls="clr-namespace:ImageButtonTest01.Control"
    xmlns:converter="clr-namespace:ImageButtonTest01.Control.Converter">
 
 
    
    
 
 
    
    
    
 
 
    

C#
ImageTextBox.CS

public class ImageTextBox : TextBox
{
    private ImageButton mClearTextButton = null;
    private ImageButton mExtendIconFontButton = null;
    private ImageButton mExtendImageButton = null;
 
 
    static ImageTextBox()
    {
        DefaultStyleKeyProperty.OverrideMetadata(typeof(ImageTextBox), new FrameworkPropertyMetadata(typeof(ImageTextBox)));
    }
 
 
    public ImageTextBox()
    {
            
    }
 
 
    public override void OnApplyTemplate()
    {
        mClearTextButton = GetTemplateChild("PART_ClearTextButton") as ImageButton;
        if (null != mClearTextButton)
        {
            mClearTextButton.Click += OnClearTextClick;
        }
 
 
        mExtendIconFontButton = GetTemplateChild("PART_ExtendIconFontButton") as ImageButton;
        if (null != mExtendIconFontButton)
        {
            mExtendIconFontButton.Click += ExtendButtonClick;
        }
 
 
        mExtendImageButton = GetTemplateChild("PART_ExtendImageButton") as ImageButton;
        if (null != mExtendIconFontButton)
        {
            mExtendImageButton.Click += ExtendButtonClick;
        }
 
 
        base.OnApplyTemplate();
    }
 
 
    private void ExtendButtonClick(object sender, RoutedEventArgs e)
    {
        RoutedEventArgs re = new RoutedEventArgs(ImageTextBox.ExtendClickEvent, this);
        RaiseEvent(re);
    }
 
 
    private void OnClearTextClick(object sender, RoutedEventArgs e)
    {
        if (sender is ImageButton)
        {
            Text = "";
        }
    }
 
 
    public static readonly DependencyProperty ImageProperty = DependencyProperty.Register(nameof(Image), typeof(ImageSource), typeof(ImageTextBox),
                                                                                            new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.AffectsRender, ImageSourceChanged));
    public ImageSource Image
    {
        get { return (ImageSource)GetValue(ImageProperty); }
        set { SetValue(ImageProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendNormalImageProperty = DependencyProperty.Register(nameof(ExtendNormalImage), typeof(ImageSource), typeof(ImageTextBox),
                                                                                    new FrameworkPropertyMetadata(null));
    public ImageSource ExtendNormalImage
    {
        get { return (ImageSource)GetValue(ExtendNormalImageProperty); }
        set { SetValue(ExtendNormalImageProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendHoverImageProperty = DependencyProperty.Register(nameof(ExtendHoverImage), typeof(ImageSource), typeof(ImageTextBox),
                                                                                    new FrameworkPropertyMetadata(null));
    public ImageSource ExtendHoverImage
    {
        get { return (ImageSource)GetValue(ExtendHoverImageProperty); }
        set { SetValue(ExtendHoverImageProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendPressedImageProperty = DependencyProperty.Register(nameof(ExtendPressedImage), typeof(ImageSource), typeof(ImageTextBox),
                                                                                    new FrameworkPropertyMetadata(null));
    public ImageSource ExtendPressedImage
    {
        get { return (ImageSource)GetValue(ExtendPressedImageProperty); }
        set { SetValue(ExtendPressedImageProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendDisabledImageProperty = DependencyProperty.Register(nameof(ExtendDisabledImage), typeof(ImageSource), typeof(ImageTextBox),
                                                                                    new FrameworkPropertyMetadata(null));
    public ImageSource ExtendDisabledImage
    {
        get { return (ImageSource)GetValue(ExtendDisabledImageProperty); }
        set { SetValue(ExtendDisabledImageProperty, value); }
    }
 
 
    public static readonly DependencyProperty PlaceHolderProperty = DependencyProperty.Register(nameof(PlaceHolder), typeof(string), 
                                                                typeof(ImageTextBox), new PropertyMetadata(""));
    public string PlaceHolder
    {
        get { return (string)GetValue(PlaceHolderProperty); }
        set { SetValue(PlaceHolderProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendIconFontTextProperty = DependencyProperty.Register(nameof(ExtendIconFontText), typeof(string),
                                                                typeof(ImageTextBox), new PropertyMetadata(""));
    public string ExtendIconFontText
    {
        get { return (string)GetValue(ExtendIconFontTextProperty); }
        set { SetValue(ExtendIconFontTextProperty, value); }
    }
 
 
    public static readonly DependencyProperty CornerRadiusProperty = DependencyProperty.Register(nameof(CornerRadius), typeof(CornerRadius), 
        typeof(ImageTextBox), new PropertyMetadata(new CornerRadius(0,0,0,0)));
    public CornerRadius CornerRadius
    {
        get { return (CornerRadius)GetValue(CornerRadiusProperty); }
        set { SetValue(CornerRadiusProperty, value); }
    }
 
 
    public static readonly DependencyProperty LeftImageWidthProperty = DependencyProperty.Register(nameof(LeftImageWidth), typeof(double),
                                                                                    typeof(ImageTextBox), new PropertyMetadata(0.0));
    public double LeftImageWidth
    {
        get { return (double)GetValue(LeftImageWidthProperty); }
        set { SetValue(LeftImageWidthProperty, value); }
    }
 
 
    private static void ImageSourceChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        ImageTextBox itb = sender as ImageTextBox;
        ImageSource image = e.NewValue as ImageSource;
 
 
        itb.SetValue(LeftImageWidthProperty, image.Width);
    }
 
 
    public static readonly RoutedEvent ExtendClickEvent = EventManager.RegisterRoutedEvent(nameof(ExtendClick), RoutingStrategy.Bubble,
                                                                        typeof(RoutedEventHandler), typeof(ImageTextBox));
 
 
    public event RoutedEventHandler ExtendClick
    {
        add { AddHandler(ExtendClickEvent, value); }
        remove { RemoveHandler(ExtendClickEvent, value); }
    }
 
 
    public static DependencyProperty ExtendButtonCommandProperty = DependencyProperty.Register(nameof(ExtendButtonCommand), typeof(ICommand), typeof(ImageTextBox));
    public ICommand ExtendButtonCommand
    {
        get { return (ICommand)GetValue(ExtendButtonCommandProperty); }
        set { SetValue(ExtendButtonCommandProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendButtonCommandParameterProperty =
                                    DependencyProperty.Register(nameof(ExtendButtonCommandParameter), typeof(object), typeof(ImageTextBox), new UIPropertyMetadata(null));
    public object ExtendButtonCommandParameter
    {
        get { return (object)GetValue(ExtendButtonCommandParameterProperty); }
        set { SetValue(ExtendButtonCommandParameterProperty, value); }
    }
 
 
    public static readonly DependencyProperty ExtendButtonCommandTargetProperty =
                                DependencyProperty.Register(nameof(ExtendButtonCommandTarget), typeof(IInputElement), typeof(ImageTextBox), new UIPropertyMetadata(null));
    public IInputElement ExtendButtonCommandTarget
    {
        get { return (IInputElement)GetValue(ExtendButtonCommandTargetProperty); }
        set { SetValue(ExtendButtonCommandTargetProperty, value); }
    }
}

转换器ImageTextBoxMarginLeftConverter.cs
public class ImageTextBoxMarginLeftConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        if (value is double)
        {
            double v = (double)value;
            return v * 3.0 / 5.0;
        }
        return 0;
    }
 
    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

使用：

                             CornerRadius="12"
                        PlaceHolder="请输入用户名"
                        ExtendIconFontText=""
                        ExtendNormalImage="Resources/Images/MS.png"
                        ExtendHoverImage="Resources/Images/MS.png"
                        ExtendPressedImage="Resources/Images/MS.png"
                        ExtendDisabledImage="Resources/Images/MS.png"
                        Text="{Binding InputText, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                        ExtendButtonCommand="{Binding BottonCommand}" ExtendButtonCommandParameter="button1 Click"/>
                             ExtendIconFontText=""
    CornerRadius="20" FontSize="20" Background="YellowGreen"
    PlaceHolder="请输入用户名"/>
                             ExtendNormalImage="Resources/Images/MS.png"
                        ExtendHoverImage="Resources/Images/MS.png"
                        ExtendPressedImage="Resources/Images/MS.png"
                        ExtendDisabledImage="Resources/Images/MS.png"
    PlaceHolder="请输入用户名"
    Image="Resources/Images/logo.png"/>
         PlaceHolder="请输入用户名" CornerRadius="20" IsEnabled="True"
    Image="Resources/Images/logo.png"/>
         PlaceHolder="请输入用户名" CornerRadius="20" IsEnabled="False"
    Image="Resources/Images/logo.png"/>