siliverlight Combox

[xujinli88]

找不到控件 我只是加了个IsSelected="True" 这是怎么回事
.xaml 页面 代码

<navigation:Page x:Class="SilverlightTest.Real" 
           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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
           mc:Ignorable="d"
           xmlns:navigation="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Navigation"
           d:DesignWidth="640" d:DesignHeight="480"
           Title="Real Page">
    <Grid x:Name="LayoutRoot" Background="White">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
            <RowDefinition Height="Auto"></RowDefinition>
        </Grid.RowDefinitions>
        <TextBlock Text="选择控件" Margin="5,10,10,10"  FontSize="18" FontWeight="Bold" Foreground="#FFBE4D4D" Grid.Row="0"></TextBlock>
        <Grid Grid.Row="1" Margin="5,0,0,5">
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
            </Grid.RowDefinitions>
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="Auto"></ColumnDefinition>
                <ColumnDefinition Width="Auto"></ColumnDefinition>
                <ColumnDefinition Width="Auto"></ColumnDefinition>
                <ColumnDefinition Width="Auto"></ColumnDefinition>
            </Grid.ColumnDefinitions>
            <TextBlock Text="字体：" Grid.Row="0" Grid.Column="0"></TextBlock>
            <ComboBox Name="fontComboBox" Width="150" ItemsSource="{Binding}" Grid.Row="0" Grid.Column="1" SelectionChanged="fontComboBox_SelectionChanged"></ComboBox>
            <TextBlock Text="大小：" Grid.Row="0" Grid.Column="2"></TextBlock>
            <ComboBox Name="fontSizeComboBox" Width="80" Grid.Row="0" Grid.Column="3" SelectionChanged="fontSizeComboBox_SelectionChanged">
                <ComboBoxItem Content="12"  IsSelected="True"></ComboBoxItem>
                <ComboBoxItem Content="13"></ComboBoxItem>
                <ComboBoxItem Content="14"></ComboBoxItem>
                <ComboBoxItem Content="15"></ComboBoxItem>
                <ComboBoxItem Content="16"></ComboBoxItem>
            </ComboBox>
            <TextBlock Name="textBlock1"  Text="测试内容" Margin="10,5,0,0" Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="4">
            </TextBlock>
            <TextBlock Name="textBlock2" Text="测试内容2" Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="4" Margin="10,5,0,0"></TextBlock>
            <TextBlock Name="textBlock3" Text="测试内容3" Grid.Row="3" Grid.Column="0" Grid.ColumnSpan="4" Margin="10,5,0,0"></TextBlock>
            <TextBlock Name="textBlock4" Text="测试内容4" Margin="10,5,0,0" Grid.Row="4" Grid.Column="0" Grid.ColumnSpan="4">
            </TextBlock>
            <TextBlock Name="textBlock5" Text="测试内容5" Margin="10,5,0,0" Grid.Row="5" Grid.Column="0" Grid.ColumnSpan="4">
            </TextBlock>
        </Grid>
    </Grid>
</navigation:Page>

后台。cs 文件

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Windows.Navigation;
using System.Collections.ObjectModel;//ObservableCollection

namespace SilverlightTest
{
    public partial class Real : Page
    {
        public Real()
        {
            InitializeComponent();
            ObservableCollection<FontFamily> fonts = new ObservableCollection<FontFamily>();
            fonts.Add(new FontFamily("Cambria"));
            fonts.Add(new FontFamily("Arial Unicode MS"));
            fonts.Add(new FontFamily("Batang"));
            fonts.Add(new FontFamily("Dotum"));
            this.fontComboBox.DataContext = fonts;//这样完成了绑定；
            this.fontComboBox.SelectedItem = new FontFamily("Cambria");//默认值
        }

        // 当用户导航到此页面时执行。
        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
        }

        private void fontComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            ComboBox cb = sender as ComboBox;
            this.textBlock1.FontFamily = (FontFamily)cb.SelectedItem;
            this.textBlock2.FontFamily = (FontFamily)cb.SelectedItem;
            this.textBlock3.FontFamily = (FontFamily)cb.SelectedItem;
            this.textBlock4.FontFamily = (FontFamily)cb.SelectedItem;
            this.textBlock5.FontFamily = (FontFamily)cb.SelectedItem;

        }

        private void fontSizeComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            
               ComboBox cb = sender as ComboBox;
                int fontSize = int.Parse(((ComboBoxItem)cb.SelectedItem).Content.ToString());
                this.textBlock1.FontSize =  double.Parse(fontSize.ToString());
                this.textBlock2.FontSize = fontSize+1;
                this.textBlock3.FontSize = fontSize+2;
                this.textBlock4.FontSize = fontSize+3;
                this.textBlock5.FontSize = fontSize + 4;
           

        }

    }
}

运行后在
fontSizeComboBox_SelectionChanged 这个地方报未将对象引用到对象的实例

[jigi330]

private void fontSizeComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
             
               ComboBox cb = sender as ComboBox;
                int fontSize = int.Parse(((ComboBoxItem)cb.SelectedItem).Content.ToString());
                if(cb.SelectedItem!=null)
                { 
                   //再设置字体?
                 }
            
 
        }

[xujinli88]

谢了你啦 搞不明白为啥会执行这个方法啊 只是开始加载