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This article focuses on "how to create DataTable objects for ADO.NET". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Now let the editor take you to learn "how to create DataTable objects for ADO.NET"!

ADO.NET can disconnect from the database for data processing through DataSet or DataTable objects, reconnect to the data source and update the data source when the data needs to be updated. The DataTable object represents a table stored in native memory, and it provides various operations on the row and column data objects in the table.

You can populate data directly from the database into DataTable objects, or you can add DataTable objects to existing DataSet objects. In the way of disconnection, the DataSet object provides the same relational data model as the relational database. The DataTable object in the DataSet object can be accessed directly in the code, and the ADO.NET object DataTable can be added or deleted. The ADO.NET object SqlDataAdapter provides the corresponding operation commands to the background database through the SelectCommand, InsertCommand, UpdateCommand, and DeleteCommand properties, and passes the required parameters. In general, you only need to provide a SELECT statement and a connection string to create a SqlDataAdapter object, and then use the SqlCommandBuilder object to generate InsertCommand, UpdateCommand, and DeleteCommand properties.

1. Create a DataTable object

You can create DataTable objects in two ways:

1) create a DataTable object through the constructor of the DataTable class, for example:

DataTable table = new DataTable ()

2) create a DataTable object through the Add method of the Tables object of DataSet, for example:

DataSet dataset = new DataSet (); DataTable table = dataset.Tables.Add ("MyTableName")

two。 Add a column to the DataTable object

The most common way to add columns to a DataTable object is through the Add method in the Column property of the DataTable object. Each column after being added is a DataColumn object.

3. Set the primary key of the DataTable object

Tables in relational databases generally have a primary key that uniquely identifies each row of records in the table. The primary key of the Datatable can be set through the PrimaryKey property of the DataTable object. The primary key can be an array of one or more DataColumn objects. For example:

DataColumn [] key = new DataColumn [1]; / / dt is a DataTable object key [0] = dt.Columns [0]; dt.PrimaryKey = key

4. Create a row in a DataTable object

Each row of the DataTable object is a DataRow object, so when creating a row, you can first use the NewRow method of the DataTable object to create a DataRow object, set the data for each column in the new row, and then use the Add method to add the DataRow object to the table.

5. Populate tables from SQL Server database into DataTable

In addition to creating the row and column information of the ADO.NET object DataTable directly, you can also populate the tables in the SQL Server database into the DataTable object through the Fill method of the DateAdapter object.

At this point, I believe you have a deeper understanding of "how to create DataTable objects for ADO.NET". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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