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This article introduces the knowledge of "how to call ADO.NET code". Many people will encounter such a dilemma in the operation of actual cases, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

To highlight the advantages of the new method, let's first introduce the "official" method of calling stored procedures in .NET. In addition, all the sample programs in this article work on the SqlServer database, and other situations are similar and will not be explained one by one in the future. All the examples in this article are in C # language.

To access the database in an application, the general step is to first declare a database connection SqlConnection, and then declare a database command SqlCommand to execute SQL statements and stored procedures. With these two objects, you can use different implementation methods to achieve your goals according to your own needs. To add, don't forget to add the following reference statement to the page: using System.Data.SqlClient. As far as executing stored procedures is concerned, if you are executing a class stored procedure, you need to populate the result into a DataSet with a DataAdapter, and then you can use the data grid control to render the result on the page; if you are executing the second and third stored procedures, you do not need this procedure, you only need to determine whether the operation has completed successfully based on the specific return.

(1) the ADO.NET code for executing a stored procedure with no parameters is as follows:

SqlConnection conn=new SqlConnection ("connectionString"); SqlDataAdapter da = new SqlDataAdapter (); da.SelectCommand = new SqlCommand (); da.SelectCommand.Connection = conn; da.SelectCommand.CommandText = "NameOfProcedure"; da.SelectCommand.CommandType = CommandType.StoredProcedure

Then just choose the appropriate way to perform this process for different purposes.

(2) the ADO.NET code that executes a stored procedure with parameters is as follows (we can declare the function calling the stored procedure as ExeProcedure (string inputdate)):

SqlConnection conn=new SqlConnection ("connectionString"); SqlDataAdapter da = new SqlDataAdapter (); da.SelectCommand = new SqlCommand (); da.SelectCommand.Connection = conn; da.SelectCommand.CommandText = "NameOfProcedure"; da.SelectCommand.CommandType = CommandType.StoredProcedure

(the above code is the same, the following is the code to be added)

Param = new SqlParameter ("@ ParameterName", SqlDbType.DateTime); param.Direction = ParameterDirection.Input; param.Value = Convert.ToDateTime (inputdate); da.SelectCommand.Parameters.Add (param)

This adds an input parameter. If you need to add output parameters:

Param = new SqlParameter ("@ ParameterName", SqlDbType.DateTime); param.Direction = ParameterDirection.Output; param.Value = Convert.ToDateTime (inputdate); da.SelectCommand.Parameters.Add (param)

To get the return value of the storage process:

Param = new SqlParameter ("@ ParameterName", SqlDbType.DateTime); param.Direction = ParameterDirection.ReturnValue; param.Value = Convert.ToDateTime (inputdate); da.SelectCommand.Parameters.Add (param)

In the above code, we can see that when there are more stored procedures or more parameters of stored procedures, this method will greatly affect the speed of development; on the other hand, if the project is relatively large, then these functions used for database logic are also a great burden in future maintenance. So, is there an improved way to solve this problem? Considering that when executing a stored procedure without parameters, you only need to pass in the name of a stored procedure to call the corresponding stored procedure, and in the SqlServer database, we can directly type a string like "stored procedure name (parameter list)" in the query analyzer to execute the stored procedure, so, can this idea be applied to the application?

So type the corresponding code in the compiler. This code is based on the code that calls stored procedures with no parameters. The specific ADO.NET code is as follows:

SqlConnection conn=new SqlConnection ("connectionString"); SqlDataAdapter da = new SqlDataAdapter (); da.SelectCommand = new SqlCommand (); da.SelectCommand.Connection = conn; da.SelectCommand.CommandText = "NameOfProcedure ('para1','para2',para3)"; da.SelectCommand.CommandType = CommandType.StoredProcedure

To make the code more representative, the * * and the second argument of the stored procedure to be called are of type string, and the third argument is integer. After the implementation, it is found that the expected results can be achieved!

That's all for "how to call ADO.NET code". Thank you for reading. If you want to know more about the industry, you can follow the website, the editor will output more high-quality practical articles for you!

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