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How to Store and Retrieve Image on SQLite: Difference between revisions
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Waldyrious (talk | contribs) (various minor fixes) |
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Images or any files can be stored in a database. Here is one way to do it using the following steps: | Images or any files can be stored in a database. Here is one way to do it using the following steps: | ||
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# Store QByteArray as a Binary Large Object in database. | # Store QByteArray as a Binary Large Object in database. | ||
For example : | For example: | ||
<code> | <code> | ||
QFile file(fileName); | |||
if (!file.open(QIODevice::ReadOnly)) return; | |||
QByteArray byteArray = file.readAll(); | |||
QSqlQuery query; | QSqlQuery query; | ||
query.prepare("INSERT INTO imgtable (imgdata) VALUES (?)"); | |||
query.addBindValue(byteArray); | |||
query.exec(); | |||
</code> | </code> | ||
Now, the image/file can be retrieved like any other data | Now, the image/file can be retrieved like any other data | ||
<code> | <code> | ||
QSqlQuery query("SELECT imgdata FROM imgtable"); | |||
query.next(); | |||
QByteArray array = query.value(0).toByteArray(); | |||
</code> | </code> | ||
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</code> | </code> | ||
It is done. Now the pixmap can be used in a | It is done. Now the pixmap can be used in a {{class|QPushButton}} as icon or in label etc. | ||
[[Category:Snippets]] | |||
[[Category:HowTo]] |
Revision as of 15:34, 16 November 2015
Images or any files can be stored in a database. Here is one way to do it using the following steps:
- Read the system file into a QByteArray.
- Store QByteArray as a Binary Large Object in database.
For example:
QFile file(fileName);
if (!file.open(QIODevice::ReadOnly)) return;
QByteArray byteArray = file.readAll();
QSqlQuery query;
query.prepare("INSERT INTO imgtable (imgdata) VALUES (?)");
query.addBindValue(byteArray);
query.exec();
Now, the image/file can be retrieved like any other data
QSqlQuery query("SELECT imgdata FROM imgtable");
query.next();
QByteArray array = query.value(0).toByteArray();
Creating a QPixmap from QByteArray :
QPixmap pixmap = QPixmap();
pixmap.loadFromData(array);
It is done. Now the pixmap can be used in a QPushButton as icon or in label etc.