计算机专业数据捆绑技术.docx

出自 《微软ado.net数据技术》The Data Binding TechnologyIn my project,I need to show the data from the DataBase,so I need to use the data binding technology which Microsoft company support.In the following ,lets discuss it together.If you are familiar with classic ASP, the declarative data binding syntax introduced in ASP.NET will be familiar to you even though the functionality is vastly different. Data binding expressions are the code you see between %# and % characters in an ASPX file. The expressions allow you to easily bind controls to data sources, as well as properties, expressions, and results from method calls exposed by the page. While this feature is easy to use, it often causes some confusion about what is allowed and whether it should be employed.Data binding basicsData binding expressions link ASP.NET page properties, server control properties, and data sources when the pages DataBind method is called. You can place data binding expressions on the value side of an attribute/value pair in the opening tag of a server control or anywhere in the page. All data binding expressions, regardless of where you place them, must be contained between %# and % characters.When used with data controls (like Repeater, DataGrid, and so forth), the expression parameter is usually a column name from the data source. However, as long as it returns a value, any valid expression may be used. Likewise, the same syntax may be used outside list controls. This includes displaying values on the page or populating control attributes.Container.DataItem is a runtime alias for the DataItem bound to a specific item. It maps to an individual item from the data source like one row from a database query or an individual element from an array. The actual data type for the DataItem is determined by the data source. So, if youre dealing with an array of integers, the DataItem will be an integer.The following list provides a quick review of the VB.NET syntax for various scenarios:%# Container.DataItem