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Đối tượng được tìm thấy trong ADO.NET Như đã đề cập trước đây, đối tượng chính được sử dụng với ADO.NET là đối tượng DataSet. Bạn có thể thấy đối tượng DataSet và tính chất của nó, phương pháp | Objects That Are Found in ADO.NET As mentioned previously the main object that is used with ADO.NET is the DataSet object. You can see the DataSet object and its properties methods and additional objects in Figure 3.1. Figure 3.1. ADO.NET has several more objects than ADO does. Take a look at Table 3.1 to see a brief description of some of the objects that you will be using during this How-To. Table 3.1. ADO.NET Data Objects That Are Used to Manipulate Data Object Purpose DataSet This object is used in conjunction with the other data controls storing the results that are returned by commands and the data adapters. Unlike the recordset from ADO and DAO the data set actually brings back a hierarchical view of the data. Using properties and collections in the DataSet object you can get overall relations individual tables rows and columns. DataTable One of the objects off of the data set the DataTable object enables you to manipulate an individual table s worth of data. The data table is similar to the recordset object that is found in ADO. DataView Using this object you can filter and sort your data keeping various views of the data. Each data table has a default view which is the starting data view that can be modified and stored in a separate data view. DataRow This object enables you to manipulate the rows of data in your data tables. This can be thought of as a cache of data that you can manipulate by adding deleting and modifying records. You can then accept the changes back to the recordset where you will then run SQL statements to update data back at the server. DataColumn As the name suggests you can get information at the column level by using the DataColumn object. You can get schema information as well as data using this object. For example if you want to create a list box of names of fields you could iterate through the DataColumn collection off a data row and retrieve all the names of the fields. PrimaryKey This object allows you to specify a primary key
