我试图在我的wpf应用程序中以这种方式在网格中显示两个画布控件。 second_canvas.margin.left 与 first_canvas.margin.right 相同。 但由于保证金属性不能用作变量,因此无法完成。 所以我尝试了" 厚度"。但是我无法将 first_canvas.margin.right 转换为厚度变量,因为它是 double 类型。所以有没有解决这个问题?
答案 0 :(得分:0)
您可以编写专用值转换器:
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Windows;
using System.Windows.Data;
namespace WpfMagic
{
class EditableMarginConverter : IValueConverter
{
private double GetMarginPartValue(Thickness margin, string defaultValue, IDictionary<string, string> instructions)
{
string sourceValue;
string value = instructions.TryGetValue(defaultValue, out sourceValue) ? sourceValue : defaultValue;
double numericalValue;
if (double.TryParse(value, out numericalValue))
{
return numericalValue;
}
return value == "left" ? margin.Left :
value == "top" ? margin.Top :
value == "right" ? margin.Right :
margin.Bottom;
}
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
Thickness inputMargin = (Thickness)value;
IDictionary<string, string> instructions = (parameter as string).Split()
.Select(s => s.Split('='))
.ToDictionary(t => t[0].ToLowerInvariant(), t => t[1].ToLowerInvariant());
Thickness outputMargin = new Thickness
{
Left = GetMarginPartValue(inputMargin, "left", instructions),
Top = GetMarginPartValue(inputMargin, "top", instructions),
Right = GetMarginPartValue(inputMargin, "right", instructions),
Bottom = GetMarginPartValue(inputMargin, "bottom", instructions)
};
return outputMargin;
}
public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
}
}
你会像这样使用它:
<StackPanel xmlns:local="clr-namespace:WpfMagic" Orientation="Horizontal">
<StackPanel.Resources>
<local:EditableMarginConverter x:Key="marginConverter"></local:EditableMarginConverter>
</StackPanel.Resources>
<Canvas x:Name="first_canvas"
Width="100"
Height="100"
Margin="0 0 10 0"
Background="Red">
</Canvas>
<Canvas x:Name="second_canvas"
Width="100"
Height="100"
Background="Green"
Margin="{Binding Margin,
ElementName=first_canvas,
Converter={StaticResource marginConverter},
ConverterParameter='Left=Right Right=0'}">
</Canvas>
</StackPanel>
这是一种可重复使用的方式,但是如果它是一次性的,你可能应该使用一些程序管道,除非你是教条主义并希望拥有完美的XAML。
答案 1 :(得分:0)
我这样简单地实现了它......
int right = system.convert.ToInt32(first_canvas.margin.right)
second_canvas.margin = new thickness(left = right)