When the crystal report is used to develop, you must first specify a database connection. But if we are engaged in three-story development, the crystal report is generally not allowed to access the database, but through your database processing layer returns to the crystal report. In fact, we can use the fields in the crystal report as a data source to completely get rid of Direct contact with the database, thereby developing a reporting system that is easy to publish and get rid of database restrictions. Of course, the use of this field is the development of the report, which has added some development processes than using the crystal report directly connected to the database operation, but I want to be relatively worth it. In the first part, I will talk about the production of this type of template, which is simple. I actually operate and capture the example. I believe that everyone will understand. If the field is set, click on the fork in the upper right corner, save this file. After the saving is, you can refer to the original way of making a report template with the database connection to make a good report template. In fact, this field definition file is simple, open to see the interval is a Tab playing bit, wait for the future You can use the text tool to do this file. In the next section, I use VB to make a complete program to give a demonstration.
