/**************************************************************************** ** (c) Copyright IBM Corp. 2007 All rights reserved. ** ** The following sample of source code ("Sample") is owned by International ** Business Machines Corporation or one of its subsidiaries ("IBM") and is ** copyrighted and licensed, not sold. You may use, copy, modify, and ** distribute the Sample in any form without payment to IBM, for the purpose of ** assisting you in the development of your applications. ** ** The Sample code is provided to you on an "AS IS" basis, without warranty of ** any kind. IBM HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR ** IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF ** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Some jurisdictions do ** not allow for the exclusion or limitation of implied warranties, so the above ** limitations or exclusions may not apply to you. IBM shall not be liable for ** any damages you suffer as a result of using, copying, modifying or ** distributing the Sample, even if IBM has been advised of the possibility of ** such damages. ***************************************************************************** ** ** SOURCE FILE NAME: DbEvent.cs ** ** SAMPLE: How to use DB2DataAdapter events: RowUpdating and RowUpdated ** with the DB2 .Net Data Provider ** ** SQL Statements USED: ** CREATE TABLE ** DROP TABLE ** INSERT ** SELECT ** ** DB2 .NET Data Provider Classes USED: ** DB2Connection ** DB2Command ** ** ***************************************************************************** ** ** Building and Running the sample program ** ** 1. Compile the DbEvent.cs file with bldapp.bat by entering the following ** at the command prompt: ** ** bldapp DbEvent ** ** or compile DbEvent.cs with the makefile by entering the following at ** the command prompt: ** ** nmake DbEvent ** ** 2. Run the DbEvent program by entering the program name at the command ** prompt: ** ** DbEvent ** ***************************************************************************** ** ** For more information on the sample programs, see the README file. ** ** For information on developing applications, see the Application ** Development Guide. ** ** For information on using SQL statements, see the SQL Reference. ** ** For the latest information on programming, compiling, and running DB2 ** applications, visit the DB2 Information Center at ** http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/index.jsp ** ****************************************************************************/ using System; using System.Data; using System.IO; using IBM.Data.DB2; class DbEvent { public static void Main(String[] args) { // Declare a DB2Connection and a DB2Command DB2Connection conn = null; DB2Command cmd = null; try { Console.WriteLine(); Console.WriteLine(" THIS SAMPLE SHOWS HOW TO USE DB2DataAdapter " + "EVENTS:\n RowUpdating and RowUpdated"); Console.WriteLine(); // Connect to a database Console.WriteLine(" Connecting to a database ..."); conn = ConnectDb(args); // Create a DB2DataAdapter, a DB2CommandBuilder and a DataSet DB2DataAdapter adp = new DB2DataAdapter(); DB2CommandBuilder cb = null; DataSet dset = new DataSet(); cmd = conn.CreateCommand(); // Create a table 'empsamp' in the SAMPLE database Console.WriteLine("\n CREATE A TABLE empsamp WITH ATTRIBUTES:\n" + " ID SMALLINT NOT NULL,\n" + " NAME VARCHAR(9),\n" + " JOB CHAR(5),\n" + " SALARY DEC(7,2),\n" + " PRIMARY KEY(ID)"); cmd.CommandText = "CREATE TABLE EMPSAMP (" + " ID SMALLINT NOT NULL," + " NAME VARCHAR(9)," + " JOB CHAR(5)," + " SALARY DEC(7,2)," + " PRIMARY KEY(ID))"; cmd.ExecuteNonQuery(); Console.WriteLine(); // Insert some rows in the empty table 'empsamp' Console.WriteLine( " INSERT THE FOLLOWING ROWS IN EMPSAMP:\n" + " (270, 'EMP1', 'CLERK', 4500),\n" + " (280, 'EMP2', 'MGR', 13500.50),\n" + " (290, 'EMP3', 'SALES', 11000.40)"); cmd.CommandText = "INSERT INTO empsamp(id, name, job, salary) " + " VALUES (270, 'EMP1', 'CLERK', 4500), "+ " (280, 'EMP2', 'MGR', 13500.50), " + " (290, 'EMP3', 'SALES', 11000.40) "; Console.WriteLine(); cmd.ExecuteNonQuery(); // Intialize the SELECT command of the DB2DataAdapter adp.SelectCommand = new DB2Command("SELECT * FROM empsamp",conn); Console.WriteLine("\n USE CLASS DB2CommandBuilder TO GENERATE" + " THE INSERT, UPDATE AND DELETE\n" + " COMMANDS FOR THE DB2DataAdapter"); // Initialize a DB2CommandBuilder instance that generates the UPDATE, // DELETE and INSERT commands for the DB2DataAdapter cb = new DB2CommandBuilder(adp); // Define the parameters for the generated UPDATE, DELETE and INSERT // commands of the DB2DataAdapter AddParameters(cb); Console.WriteLine("\n " + "FILL THE DATASET WITH THE Fill METHOD OF " + "DB2DataAdapter"); // Fill the DataSet with the data in table 'empsamp' adp.Fill(dset,"empsamp"); // Make changes to the DataSet and respond to the RowUpdating and // RowUpdated events raised before and after the Update() method of // DB2DataAdapter is processed for each row EventHandler(adp,dset); // Drop the table 'empsamp' cmd.CommandText = "DROP TABLE empsamp"; cmd.ExecuteNonQuery(); // Disconnect from the database Console.WriteLine("\n Disconnect from the database"); conn.Close(); } catch(Exception e) { cmd.CommandText = "DROP TABLE empsamp"; cmd.ExecuteNonQuery(); conn.Close(); Console.WriteLine(e.Message); } } // Helper method: This method establishes a connection to a database public static DB2Connection ConnectDb(String[] argv) { String server = ""; String alias = ""; String userId = ""; String password = ""; Int32 portNumber = -1; String connectString; if( argv.Length > 5 || ( argv.Length == 1 && ( String.Compare(argv[0],"?") == 0 || String.Compare(argv[0],"-?") == 0 || String.Compare(argv[0],"/?") == 0 || String.Compare(argv[0],"-h",true) == 0 || String.Compare(argv[0],"/h",true) == 0 || String.Compare(argv[0],"-help",true) == 0 || String.Compare(argv[0],"/help",true) == 0 ) ) ) { throw new Exception( "Usage: prog_name [dbAlias] [userId passwd] \n" + " prog_name [dbAlias] server portNum userId passwd"); } switch (argv.Length) { case 0: // Use all defaults alias = "sample"; userId = ""; password = ""; break; case 1: // dbAlias specified alias = argv[0]; userId = ""; password = ""; break; case 2: // userId & passwd specified alias = "sample"; userId = argv[0]; password = argv[1]; break; case 3: // dbAlias, userId & passwd specified alias = argv[0]; userId = argv[1]; password = argv[2]; break; case 4: // use default dbAlias alias = "sample"; server = argv[0]; portNumber = Convert.ToInt32(argv[1]); userId = argv[2]; password = argv[3]; break; case 5: // everything specified alias = argv[0]; server = argv[1]; portNumber = Convert.ToInt32(argv[2]); userId = argv[3]; password = argv[4]; break; } if(portNumber==-1) { connectString = "Database=" + alias; } else { connectString = "Server=" + server + ":" + portNumber + ";Database=" + alias; } if(userId != "") { connectString += ";UID=" + userId + ";PWD=" + password; } DB2Connection conn = new DB2Connection(connectString); conn.Open(); Console.WriteLine(" Connected to the " + alias + " database"); return conn; } // ConnectDb // This method defines the parameters for the UPDATE, DELETE and INSERT // commands of the DB2DataAdapter public static void AddParameters(DB2CommandBuilder cb) { try { // Define the parameters for the INSERT command in different ways cb.GetInsertCommand().Parameters.Add("@empid", DB2Type.SmallInt, 5, "ID").SourceVersion = DataRowVersion.Original; cb.GetInsertCommand().Parameters.Add( new DB2Parameter("@empname", DB2Type.VarChar, 9, ParameterDirection.Input, false, 0, 0, "NAME", DataRowVersion.Current, "")); cb.GetInsertCommand().Parameters.Add(new DB2Parameter("@empjob", DB2Type.Char, 5, "JOB")); cb.GetInsertCommand().Parameters.Add("@empsalary", DB2Type.Decimal, 7); // Define the parameters for the UPDATE command in different ways cb.GetUpdateCommand().Parameters.Add( new DB2Parameter("@empname", DB2Type.VarChar, 9)); cb.GetUpdateCommand().Parameters.Add("@empsalary", DB2Type.Decimal, 7, "SALARY"); cb.GetUpdateCommand().Parameters.Add("@empid", DB2Type.SmallInt, 5).SourceVersion = DataRowVersion.Original; DB2Parameter param = new DB2Parameter("@empjob", DB2Type.Char); cb.GetUpdateCommand().Parameters.Add(param); // Define the parameter for the DELETE command cb.GetDeleteCommand().Parameters.Add("@empid", DB2Type.SmallInt).SourceVersion = DataRowVersion.Original; } catch (Exception e) { Console.WriteLine(e.Message); } } // AddParameters // This method creates and demonstrates the use of event handlers public static void EventHandler(DB2DataAdapter adp, DataSet dset) { try { // Add event handlers. adp.RowUpdating += new DB2RowUpdatingEventHandler(UpdatingRow); adp.RowUpdated += new DB2RowUpdatedEventHandler(UpdatedRow); // Make changes to the DataSet Console.WriteLine("\n MAKE CHANGES TO THE DATASET"); int i; for(i=0; i<dset.Tables["empsamp"].Rows.Count; i++) { if(((Int16)dset.Tables["empsamp"].Rows[i]["id"]) == 270) { dset.Tables["empsamp"].Rows[i]["name"] = "LARRY"; dset.Tables["empsamp"].Rows[i]["job"] = "MGR"; dset.Tables["empsamp"].Rows[i]["salary"] = 3500; break; } } for(i=0; i<dset.Tables["empsamp"].Rows.Count; i++) { if(((Int16)dset.Tables["empsamp"].Rows[i]["id"]) == 290) { dset.Tables["empsamp"].Rows[i].Delete(); break; } } // Update 'empsamp' to reflect the changes made to the Dataset // and in the process, raise events: RowUpdating and RowUpdated Console.WriteLine("\n " + "UPDATE 'empsamp' TO REFLECT CHANGES MADE TO THE" + " DATASET,\n IN THE PROCESS INVOKING EVENTS: " + "RowUpdating and RowUpdated"); adp.Update(dset,"empsamp"); Console.WriteLine("\n EMPSAMP UPDATED"); // Remove event handlers. adp.RowUpdating -= new DB2RowUpdatingEventHandler(UpdatingRow); adp.RowUpdated -= new DB2RowUpdatedEventHandler(UpdatedRow); } catch (Exception e) { Console.WriteLine(e.Message); } } // EventHandler // This method handles the 'RowUpdating' event public static void UpdatingRow(Object sender, DB2RowUpdatingEventArgs args) { // Display what type of operation is to be performed Console.WriteLine("\n EVENT: RowUpdating"); Console.WriteLine("\n ATTEMPTING TO " + args.StatementType.ToString().ToUpper() + " THIS ROW\n"); // Display contents of the row before it is updated or deleted if (args.StatementType == StatementType.Delete || args.StatementType == StatementType.Update) { DisplayRow(args.Row,DataRowVersion.Original); } } // UpdatingRow // This method handles the 'RowUpdated' event public static void UpdatedRow(Object sender, DB2RowUpdatedEventArgs args) { Console.WriteLine("\n EVENT: RowUpdated"); // Check if errors occured when the row was being updated if (args.Status == UpdateStatus.ErrorsOccurred) { // Skip updating this row and proceed to updating the next row Console.WriteLine("\n AN ERROR OCCURRED WHILE UPDATING THIS ROW"); args.Row.RowError = args.Errors.Message; args.Status = UpdateStatus.SkipCurrentRow; } else { Console.WriteLine("\n THE " + args.StatementType.ToString().ToUpper() + " OPERATION WAS PERFORMED SUCCESFULLY"); // Display contents of the row after if has been updated if(args.StatementType == StatementType.Update) { Console.WriteLine("\n DETAILS OF ROW AFTER UPDATE:\n"); DisplayRow(args.Row,DataRowVersion.Current); } } } // UpdatedRow // Helper method: This method displays the contents of a DataRow public static void DisplayRow(DataRow row, DataRowVersion version) { // Obtain the DataTable corresponding to the DataRow DataTable table = row.Table; // Display column names Console.Write(" "); foreach(DataColumn col in table.Columns) { Console.Write(" " + col.ColumnName); } Console.WriteLine(); Console.Write(" "); foreach(DataColumn col in table.Columns) { int length = 8; if(col.DataType == Type.GetType("System.Int32") || col.DataType == Type.GetType("System.Int16")) { length = 3; } else if(col.DataType == Type.GetType("System.String")) { length = 7; } for(int i = 0; i < length; i++) { Console.Write("-"); } Console.Write(" "); } Console.WriteLine(); Console.Write(" "); // Display column entries of each row foreach(DataColumn col in table.Columns) { Object data = row[col.ColumnName, version]; if(data is Int32 || data is Int16) { Console.Write(" " + data.ToString().PadRight(3)); } else if (data is String) { Console.Write(" " + ((String)data).PadRight(7)); } else { String str = String.Format("{0:f2}" ,data); Console.Write(" " + str.PadLeft(8)); } } Console.WriteLine(); } // DisplayRow } // DbEvent