Silverlight 4常用StringFormat格式总结

在Silverlight项目中，经常会根据需求的不同，提供不同的字符格式到客户端。这篇文章总结了目前Silverlight 4常用StringFormat绑定字符格式，方便大家在以后的开发中调用参考。

早期的格式转换方法

在Silverlight 4之前的版本，通常修改字符格式是通过实现IValueConverter接口，在IValueConverter接口中包含有两个方法：

1. Convert， 在绑定源数据传送到客户端显示前，转换修改数据；

2. ConvertBack，在目标数据传送到绑定源数据前，转换修改数据，该方法仅被用于“TwoWay”绑定模式；

例如，根据布尔型判断实现控件是否显示在客户端，下面是一个简单的转换代码，通过实现IValueConverter，判断控件Visibility属性值。

1 public class VisibilityConverter:IValueConverter
2
3 {
4
5 public object Convert( object value,TypetargetType, object parameter,CultureInfoculture)
6
7 {
8
9 bool visibility = ( bool )value;
10
11 return visibility ? Visibility.Visible:Visibility.Collapsed;
12
13 }
14
15 public object ConvertBack( object value,TypetargetType, object parameter,CultureInfoculture)
16
17 {
18
19 Visibilityvisibility = (Visibility)value;
20
21 return (visibility == Visibility.Visible);
22
23 }
24
25 }

Silverlight 4的StringFormat属性

在Silverlight 4中，数据绑定SDK提供一个“StringFormat”的属性，该属性允许开发人员自由定义输出字符格式，例如，DataPicker控件，该控件提供SelectedDateFormat属性，控制其输出格式“短格式”或“长格式”。

SelectedDateFormat="Short", “默认”

SelectedDateFormat="Long"

而如果需要输出“April 01, 2011”格式，则无法使用SelectedDateFormat控制其格式，这时可以使用StringFormat属性完成需求。

<toolkit:DatePicker SelectedDate="{Binding DemoDate,Mode=TwoWay, StringFormat='MMM d, yyyy'}" />

再例如，早期实现一段文字绑定信息需要按照以下格式操作：

<TextBlock Text=”当前登录用户: ”/>

<TextBlock Text=“{Binding Name}”/>

输出: 当前登录用户Jv9

在Silverlight 4中使用StringFormat属性，可以简单的实现如下:

<TextBlock Text=“{Binding Name, StringFormat=’当前登录用户: /{0/}’}”>

这样实现简单而又方便。

对于StringFormat属性的使用方法还有很多，下面使用实例演示常用的属性：

1 < Grid x:Name ="LayoutRoot" >
2 < ScrollViewer x:Name ="PageScrollViewer" Style ="{StaticResourcePageScrollViewerStyle}" >
3 < StackPanel Orientation ="Horizontal" >
4 < StackPanel x:Name ="ContentStackPanel" >
5 < TextBlock FontSize ="16" TextWrapping ="Wrap" Text ="StringFormat和字符串格式" Margin ="8" />
6 < Border BorderBrush ="LightGray" BorderThickness ="1" Width ="300" Margin ="5" HorizontalAlignment ="Left" >
7 < StackPanel Orientation ="Vertical" Margin ="5" >
8 < TextBox x:Name ="txtSource" Width ="125" HorizontalAlignment ="Left" />
9 < TextBlock TextWrapping ="Wrap" Text ="StringFormat='正在输入&quot;/{0/}&quot;." FontWeight ="Bold" Margin ="0,4,0,2" />
10 < TextBlock Text ="{BindingText,ElementName=txtSource,StringFormat='正在输入&quot;/{0/}&quot;.'}" TextWrapping ="Wrap" Margin ="0,0,0,4" />
11 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0/,20/}" FontWeight ="Bold" Margin ="0,4,0,2" />
12 < TextBlock Text ="{BindingText,ElementName=txtSource,StringFormat=/{0/,20/}}" TextWrapping ="Wrap" Margin ="0,0,0,4" />
13 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0/,-20/}" FontWeight ="Bold" Margin ="0,4,0,2" />
14 < TextBlock Text ="{BindingText,ElementName=txtSource,StringFormat=/{0/,-20/}}" TextWrapping ="Wrap" Margin ="0,0,0,4" />
15 </ StackPanel >
16 </ Border >
17
18 < StackPanel x:Name ="DatePanel" >
19 < TextBlock Text ="StringFormat和日期格式" Margin ="8" FontSize ="16" />
20 < Border BorderBrush ="LightGray" BorderThickness ="1" Width ="300" Margin ="5" HorizontalAlignment ="Left" >
21 < StackPanel DataContext ="{StaticResourceSampleDate}" >
22 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=f" FontWeight ="Bold" Margin ="0,4,0,2" />
23 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=f}" Margin ="8,0" />
24 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=F" FontWeight ="Bold" Margin ="0,4,0,2" />
25 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=F}" Margin ="8,0" />
26 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=g" FontWeight ="Bold" Margin ="0,4,0,2" />
27 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=g}" Margin ="8,0" />
28 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=G" FontWeight ="Bold" Margin ="0,4,0,2" />
29 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=G}" Margin ="8,0" />
30 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=m" FontWeight ="Bold" Margin ="0,4,0,2" />
31 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=m}" Margin ="8,0" />
32 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=y" FontWeight ="Bold" Margin ="0,4,0,2" />
33 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=y}" Margin ="8,0" />
34 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=t" FontWeight ="Bold" Margin ="0,4,0,2" />
35 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=t}" Margin ="8,0" />
36 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=T" FontWeight ="Bold" Margin ="0,4,0,2" />
37 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=T}" Margin ="8,0" />
38 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=u" FontWeight ="Bold" Margin ="0,4,0,2" />
39 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=u}" Margin ="8,0" />
40 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=o" FontWeight ="Bold" Margin ="0,4,0,2" />
41 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=o}" Margin ="8,0" />
42 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=MM/dd/yy" FontWeight ="Bold" Margin ="0,4,0,2" />
43 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=MM/dd/yy}" Margin ="8,0" />
44 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=MMMMdd/,yyyyg" FontWeight ="Bold" Margin ="0,4,0,2" />
45 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=MMMMdd/,yyyyg}" Margin ="8,0" />
46 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=hh:mm:ss.ffftt" FontWeight ="Bold" Margin ="0,4,0,2" />
47 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=hh:mm:ss.ffftt}" Margin ="8,0" />
48 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:r/}" FontWeight ="Bold" Margin ="0,4,0,2" />
49 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat=/{0:r/}}" Margin ="8,0" />
50 < TextBlock TextWrapping ="Wrap" Text ="StringFormat='MMMd,yyyy'" FontWeight ="Bold" Margin ="0,4,0,2" />
51 < TextBlock TextWrapping ="Wrap" Text ="{BindingCurrentDateTime,StringFormat='MMMd,yyyy'}" Margin ="8,0" />
52 </ StackPanel >
53 </ Border >
54 </ StackPanel >
55 </ StackPanel >
56 < StackPanel Orientation ="Vertical" >
57 < TextBlock Text ="StringFormat和数字演示" Margin ="8" FontSize ="16" />
58 < Border BorderBrush ="LightGray" BorderThickness ="1" Width ="300" Margin ="5" HorizontalAlignment ="Left" >
59 < StackPanel Orientation ="Vertical" Margin ="5" >
60 < Grid >
61 < Grid.RowDefinitions >
62 < RowDefinition Height ="Auto" />
63 < RowDefinition Height ="Auto" />
64 </ Grid.RowDefinitions >
65 < Grid.ColumnDefinitions >
66 < ColumnDefinition Width ="Auto" MinWidth ="18" />
67 < ColumnDefinition />
68 < ColumnDefinition Width ="Auto" MinWidth ="28" />
69 </ Grid.ColumnDefinitions >
70 < TextBlock Text ="1" HorizontalAlignment ="Left" d:LayoutOverrides ="Height" />
71 < TextBlock Text ="100,000" d:LayoutOverrides ="Width,Height" Grid.Column ="2" Margin ="0" />
72 < Slider x:Name ="BigNumSlider" Margin ="0" d:LayoutOverrides ="Height" Grid.ColumnSpan ="3" Grid.Row ="1" Maximum ="100000" Minimum ="1" Value ="50000" />
73 </ Grid >
74 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=c" FontWeight ="Bold" Margin ="0,4,0,2" />
75 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat=c}" Margin ="8,0" />
76 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=目前拥有现金/{0:C0/}" FontWeight ="Bold" Margin ="0,4,0,2" />
77 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat=目前拥有现金/{0:C0/}}" Margin ="8,0" />
78 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=e" FontWeight ="Bold" Margin ="0,4,0,2" />
79 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat=e}" Margin ="8,0" />
80 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:E4/}" FontWeight ="Bold" Margin ="0,4,0,2" />
81 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat=/{0:E4/}}" Margin ="8,0" />
82 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=n" FontWeight ="Bold" Margin ="0,4,0,2" />
83 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat=n}" Margin ="8,0" />
84 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:N0/}" FontWeight ="Bold" Margin ="0,4,0,2" />
85 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat=/{0:N0/}}" Margin ="8,0" />
86 < TextBlock TextWrapping ="Wrap" Text ="StringFormat='###,###.##'" FontWeight ="Bold" Margin ="0,4,0,2" />
87 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider,Mode=TwoWay,StringFormat='###,###.##'}" Margin ="8,0" />
88 </ StackPanel >
89 </ Border >
90 < Border BorderBrush ="LightGray" BorderThickness ="1" Width ="300" Margin ="5" HorizontalAlignment ="Left" >
91 < StackPanel Orientation ="Vertical" Margin ="5" >
92 < Grid >
93 < Grid.RowDefinitions >
94 < RowDefinition Height ="Auto" />
95 < RowDefinition Height ="Auto" />
96 </ Grid.RowDefinitions >
97 < Grid.ColumnDefinitions >
98 < ColumnDefinition Width ="Auto" MinWidth ="18" />
99 < ColumnDefinition />
100 < ColumnDefinition Width ="Auto" MinWidth ="28" />
101 </ Grid.ColumnDefinitions >
102 < TextBlock Text ="-1" HorizontalAlignment ="Left" d:LayoutOverrides ="Height" />
103 < TextBlock Text ="1" d:LayoutOverrides ="Width,Height" Grid.Column ="2" Margin ="0" />
104 < Slider x:Name ="BigNumSlider1" Margin ="0" d:LayoutOverrides ="Height" Grid.ColumnSpan ="3" Grid.Row ="1" Maximum ="1" Minimum ="-1" Value ="0.2" LargeChange ="0.1" SmallChange ="0.01" />
105 </ Grid >
106 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=n" FontWeight ="Bold" Margin ="0,4,0,2" />
107 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider1,Mode=TwoWay,StringFormat=n}" Margin ="8,0" />
108 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:N4/}" FontWeight ="Bold" Margin ="0,4,0,2" />
109 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider1,Mode=TwoWay,StringFormat=/{0:N4/}}" Margin ="8,0" />
110 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=p" FontWeight ="Bold" Margin ="0,4,0,2" />
111 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider1,Mode=TwoWay,StringFormat=p}" Margin ="8,0" />
112 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:P0/}" FontWeight ="Bold" Margin ="0,4,0,2" />
113 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider1,Mode=TwoWay,StringFormat=/{0:P0/}}" Margin ="8,0" />
114 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:E5/}" FontWeight ="Bold" Margin ="0,4,0,2" />
115 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider1,Mode=TwoWay,StringFormat=/{0:E5/}}" Margin ="8,0" />
116 < TextBlock TextWrapping ="Wrap" Text ="StringFormat=/{0:C3/}" FontWeight ="Bold" Margin ="0,4,0,2" />
117 < TextBox TextWrapping ="Wrap" Text ="{BindingValue,ElementName=BigNumSlider1,Mode=TwoWay,StringFormat=/{0:C3/}}" Margin ="8,0" />
118 </ StackPanel >
119 </ Border >
120 </ StackPanel >
121
122 </ StackPanel >
123 </ ScrollViewer >
124 </ Grid >

源代码下载

在线演示

欢迎大家加入“专注Silverlight”QQ技术群，欢迎大家加入一起学习讨论Silverlight&WPF&Widnows Phone开发技术。
22308706(一群) 超级群500人
37891947(二群) 超级群500人
100844510(三群) 高级群200人
32679922(四群) 超级群500人
23413513(五群) 高级群200人
32679955(六群) 超级群500人
61267622(七群) 超级群500人
88585140(八群) 超级群500人
128043302(九群 企业应用开发推荐群) 高级群200人
101364438(十群) 超级群500人
68435160(十一群 企业应用开发推荐群)超级群500人