Crystal Reports in ASP.NET

Crystal Reports in ASP.NET

Crystal Reports is the standard reporting tool for Visual Studio .NET used to display data of presentation quality. You can display multiple-level totals, charts to analyze data, and much more in Crystal Reports. Creating a Crystal Report requires minimal coding since it is created in Designer interface. It is available as an integrated feature of Microsoft Visual Studio .NET, Borland Delphi, and C#Builder.

Advantages of Crystal Reports

Some of the major advantages of using Crystal Reports are:

1. Rapid report development since the designer interface would ease the coding work for the programmer.

2. Can extend it to complicated reports with interactive charts and enhance the understanding of the business model

3. Exposes a report object model, can interact with other controls on the ASP.NET Web form

4. Can programmatically export the reports into widely used formats like .pdf, .doc, .xls, .html and .rtf

Implementation Models

Crystal Reports need database drivers to connect to the data source for accessing data. Crystal Reports in .net support two methods to access data from a data source:

The Pull Method

When this model is used to access data from the data source, the database driver directly retrieves the data from the data source. This model does not require the developer to write code for creating a connection and retrieving data from the data source. It is the Crystal report that manages the SQL commands for connecting by using the specified driver.

The Push Method

When this model is used to access data from data source, the developer writes the code to connect to the data source and retrieve data. The data from the data source is cached in dataset and multiple crystal reports accesses data from the dataset. The performance can be optimized in this manner by using connection sharing and manually limiting the number of records that are passed on to the report.
                                             

Crystal Reports Types

Crystal Report Designer can load reports that are included into the project as well as those that are independent of the project.

Strongly-typed Report

When you add a report file into the project, it becomes a "strongly-typed" report. In this case, you will have the advantage of directly creating an instance of the report object, which could reduce a few lines of code, and cache it to improve performance. The related .vb file, which is hidden, can be viewed using the editor's "show all files" icon in the Solution Explorer.

Un-Typed Report

Those reports that are not included into the project are "un-typed" reports. In this case, you will have to create an instance of the Crystal Report Engine's "ReportDocument" object and manually load the report into it.

Creating Crystal Reports

You can create a Crystal Report by using three methods:

1. Manually i.e. from a blank document
2. Using Standard Report Expert
3. From an existing report

Using Pull Method

Creating Crystal Reports Manually.

We would use the following steps to implement Crystal Reports using the Pull Model:

1. Create the .rpt file (from scratch) and set the necessary database connections using the Crystal Report Designer interface.

2. Place a CrystalReportViewer control from the toolbox on the .aspx page and set its properties to point to the .rpt file that we created in the previous step.

3. Call the databind method from your code behind page.

I. Steps to create the report i.e. the .rpt file

1) Add a new Crystal Report to the web form by right clicking on the "Solution Explorer", selecting "Add" --> "Add New Item" --> "Crystal Report".

2) On the "Crystal Report Gallery" pop up, select the "As a Blank Report" radio button and click "ok".

3) This should open up the Report File in the Crystal Report Designer.

4) Right click on the "Details Section" of the report, and select "Database" -> "Add/Remove Database".

5) In the "Database Expert" pop up window, expand the "OLE DB (ADO)" option by clicking the "+" sign, which should bring up another "OLE DB (ADO)" pop up.

6) In the "OLE DB (ADO)" pop up, Select "Microsoft OLE DB Provider for SQL Server" and click Next.

7) Specify the connection information.

8) Click "Next" and then click "Finish"

9) Now you should be able to see the Database Expert showing the table that have been selected

10) Expand the "Pubs" database, expand the "Tables", select the "Stores" table and click on ">" to include it into the "Selected Tables" section.

Note: If you add more than one table in the database Expert and the added tables have matching fields, when you click the OK button after adding the tables, the links between the added tables is displayed under the Links tab. You can remove the link by clicking the Clear Links button.

11) Now the Field Explorer should show you the selected table and its fields under the "Database Fields" section, in the left window.

12) Drag and drop the required fields into the "Details" section of the report. The field names would automatically appear in the "Page Header" section of the report. If you want to modify the header text then right click on the text of the "Page Header" section, select "Edit Text Object" option and edit it.

13) Save it and we are through.