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You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application.
The application contains a ListBox control named lbxItems that is data-bound to a collection of objects. Each object has a DisplayValue property.
You add a Button control to the application.
You need to ensure that the Content property of the Button control is data-bound to the DisplayValue property of the selected item of lbxItems.
Which binding expression should you use?（）

您需要创建一个将用于部署 Windows 7 的虚拟硬盘 （VHD）文件。该解决方案必须将使用VHD造成的性能影响减到最少。您应该创建哪种类型的VHD？（） 不同的磁盘。 动态扩充的磁盘。 固定大小的磁盘。 快照。 施工成本核算的基本环节中，不包括（）。 衡量成本降低的实际成果，对成本指标完成情况进行总结和评价。 计算出施工费用的实际发生额。 计算出该施工项目的总成本和单位成本。 按照规定的成本开支范围对施工费用进行归集和分配。 You create a Web site that you must copy from a development server to a testing server, along with all source files. You do not have terminal access to the testing server. You need to create the virtual directory. Then you must copy the Web site to the virtual directory on the testing server without precompiling the site. What should you do?（） Use the Publish Web tool.。 Use the Copy Web tool.。 Use the command line to XCOPY the files.。 Create a Web Setup project.。 创建索引的命令关键字为（），删除索引的命令关键字为（）。 You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5.  The application allows users to post comments to a page that can be viewed by other users.  You add a SqlDataSource control named SqlDS1. You write the following code segment. （Line numbers are included for reference only.）  01 Private Sub SaveComment（）  02 Dim ipaddr As String  03  04 SqlDS1.InsertParameters（"IPAddress"）.DefaultValue = ipaddr  05 ’ ...  06 SqlDS1.Insert（）  07 End Sub  You need to ensure that the IP Address of each user who posts a comment is captured along with the user’s comment.  Which code segment should you insert at line 03？（） A。 B。 C。 D。

You use Microsoft Visual Studio 2010 and Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application.
The application contains a ListBox control named lbxItems that is data-bound to a collection of objects. Each object has a DisplayValue property.
You add a Button control to the application.
You need to ensure that the Content property of the Button control is data-bound to the DisplayValue property of the selected item of lbxItems.
Which binding expression should you use?（）