FIRST WORKFLOW in Visual C#

Creator Data Matrix 2d barcode in Visual C# FIRST WORKFLOW

Make sure the name parameter to the Add method is the same as the public property name. For example, the first parameter to be added is PartNumber, and PartNumber is a public property of the workflow. If the parameters don t match, the value can t be passed. Also make sure to include CDate when passing a date value, and CInt when passing an integer value; otherwise, you ll get an Invalid Value error. Finally, change the CreateWorkflow line to the following: workflowInstance = workflowRuntime.CreateWorkflow(GetType(PurchaseOrderProcess), Parameters) This passes the Parameters dictionary object to the workflow. Following is the completed Sub Main code necessary to prompt for, read, and pass the necessary parameters for a purchase order: Shared Sub Main() Dim Parameters As New Dictionary(Of String, Object) Console.Write("("Enter the Part Number")") Parameters.Add("("PartNumber",",Console.ReadLine) Console.Write("Enter the Purchase Date:") Parameters.Add("PurchaseDate", Cdate(Console.ReadLine)) Console.Write("Enter the Expected Date:") Parameters.Add("ExpectedDate", Cdate(Console.ReadLine)) Console.Write("Enter the Buyer Login:") Parameters.Add("BuyerLogin", Console.ReadLine) Console.Write("Enter the Buyer Name:") Parameters.Add("BuyerName", Console.ReadLine) Console.Write("Enter the Quantity Ordered:") Parameters.Add("QuantityOrdered", Cint(Console.ReadLine)) Using workflowRuntime As New WorkflowRuntime() AddHandler workflowRuntime.WorkflowCompleted, AddressOf OnWorkflowCompleted AddHandler workflowRuntime.WorkflowTerminated, AddressOf OnWorkflowTerminated Dim workflowInstance As WorkflowInstance workflowInstance = workflowRuntime.CreateWorkflow( GetType(PurchaseOrderProcess), Parameters) workflowInstance.Start() WaitHandle.WaitOne() End Using End Sub The last change to be made to Module1.vb is to change the sub OnWorkflowCompleted. When the workflow is completed, the purchase order number is to be given back to the user. Change the OnWorkflowCompleted sub, as follows: Shared Sub OnWorkflowCompleted(ByVal sender As Object, ByVal e As WorkflowCompletedEventArgs) MsgBox("Purchase Order Number is: " & e.OutputParameters("PurchaseOrderNumber").ToString) WaitHandle.Set() End Sub

Make sure the WaitHandle.Set() line is after the message box line; otherwise, your workflow will complete before the message box can appear. The last steps in this process are to add a Code activity to the workflow, and to add all necessary code to insert the purchase order, determine the purchase order number, and then provide that purchase order number to the user. To start, add a Code activity to the workflow and name the Code activity AddPurchaseOrder. Generate handlers for the Code activity. Now, within the AddPurchaseOrder_ExecuteCode sub, you must build the SQL statement and execute it against the database to insert the purchase order record. Before you can interact with a database, you must determine the connection string that s necessary. Because this is a Windows-based application instead of a Web-based application, an app.config file can hold settings that you want to use later. Click the My Project link within Solution Explorer, which opens a form with several tabs down the left side. Click the Settings tab and a new page appears. However, this page only has a link that says This project does not contain a default settings file. Click here to create one. Click this link to create the app.config file for this project. When the settings form appears, change the name value in the first row to ConnString and use the drop-down list under Type to change the type to ConnectionString (the last one in the list). Your settings form looks like Figure 2-13.

Figure 2-13. Application settings within My Project Click the ellipse at the right side of the Value column for the first row. This allows you to choose a data source. Choose Microsoft SQL Server and click Continue, as shown in Figure 2-14.

When the Connection Properties form appears, you can enter (local) as the server name. Leave Windows Authentication checked. This assumes that the account you re logged into on your computer is a SQL Server user and can use the Purchasing database. Click the drop-down for Database Name and choose Purchasing. If you don t see the Purchasing database, either you didn t enter (local) correctly (this must match exactly), or your login doesn t have access to the Purchasing database. If you see other databases, but not Purchasing, then the latter is correct; if you don t see any database names, then you didn t enter the Server Name correctly. If you re encountering a problem with using (local), you can use the drop-down list under Server Name to find your server s name. The completed connection properties look like Figure 2-15.

Figure 2-15. Completed connection properties Now the connection string has been established. Click the Save button to save the project properties and close the project properties. Next, view the code for the workflow and add a new sub called SQLInsertUpdate. This sub will do the work to insert the record and update the purchase order number. You ll call this