- #FORMAT BLOB IMAGE DELPHI HOW TO#
- #FORMAT BLOB IMAGE DELPHI CODE#
A good example is to highlight specific fields or records. To this end, the sample uses the LoadFromFile method and the TOpenDialog object.There are many reasons you might want to customize the output of a grid.
Click on the Load Picture button to load a picture from a file into the BLOB field of the current record. To this end, the sample uses the SaveToFile method and the TSaveDialog object. Click on the Save Picture button to save the picture contained on the BLOB field to a file. To this end the sample uses the Clear method. Click on the Clear Picture button to clear the picture of the current record. To this end, the database navigator is linked with the dsCategories dataset by setting the DataSource property of DBNavigator1 to dsCategories. Use the TDBNavigator object to view and manipulate records. Moreover, the Picture field of the record is displayed on the Image1 component using the LoadFromStream method. The Description field of this record will be displayed on the DBMemo1. Once the DBGrid1 is filled, you can interact with the sample in the following ways: Then, the sample displays the Categories table using a TDBGrid component. When you select an item of the combo box, the sample uses the Open method of qCategories in order to execute the SQL statement that retrieves the Categories table from the database. Click on the Use Connection Definition combo box and select an option in order to define a connection. The BLOB stream is used to read the picture contained on the BLOB field of each record. When you run the application, the sample uses the CreateBlobStream method of TFDQuery with its mode set to bmRead in order to create a read-only BLOB stream. Set the DataField property of DBMemo1 to Description. Set the DataSource property of DBMemo1 to dsCategories. This component is used to display the Description field of the dataset. 
The DataSource property of DBGrid1 is set to dsCategories. The DataSet property of dsCategories is set to qCategories. To this end, the following setup is needed: In this sample, it is used to provide communication between the dataset and the grid where the dataset is displayed. This component provides an interface between a dataset component and data-aware controls on a form. A TDataSource object named dsCategories. It specifies the SQL statement to execute for the query. Set the SQL property to select * from. Configure the Connection property to specify the FireDAC connection object that is used to connect to a DBMS. This component is used to implement a dataset capable of executing SQL queries. 
Navigate to the location given above and open Blobs.dproj.īefore running the sample, the main components are configured at design time using the Object Inspector as follows:. In this sample, the BLOB stream is used to read the picture contained on each BLOB field of each record of the Categories table. To this end, the sample uses the CreateBlobStream method of TFDQuery to create a read-only BLOB stream. The Blobs sample shows you how to create a BLOB stream for reading and/or writing the value of a specific BLOB field on a specific record. Search by name into the samples repositories according to your RAD Studio version.
You can find Delphi code samples in GitHub Repositories.Object Pascal\Database\FireDAC\Samples\Comp Layer\TFDQuery\Blobs.Start | Programs | Embarcadero RAD Studio Sydney | Samples and then navigate to:.You can find the Blobs sample project at:
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