QSqlError Class

The QSqlError class provides SQL database error information. 更多...

头: #include <QSqlError>

公共类型

enum ErrorType { NoError, ConnectionError, StatementError, TransactionError, UnknownError }

公共函数

QSqlError (const QString & driverText = QString(), const QString & databaseText = QString(), ErrorType type = NoError, int number = -1)
QSqlError (const QSqlError & other )
~QSqlError ()
QString databaseText () const
QString driverText () const
bool isValid () const
int number () const
void setDatabaseText (const QString & databaseText )
void setDriverText (const QString & driverText )
void setNumber (int number )
void setType (ErrorType type )
QString text () const
ErrorType type () const
QSqlError & operator= (const QSqlError & other )

详细描述

The QSqlError class provides SQL database error information.

A QSqlError object can provide database-specific error data, including the driverText () 和 databaseText () messages (or both concatenated together as text ()), and the error number () 和 type (). The functions all have setters so that you can create and return QSqlError objects from your own classes, for example from your own SQL drivers.

另请参阅 QSqlDatabase::lastError () 和 QSqlQuery::lastError ().

成员类型文档编制

enum QSqlError:: ErrorType

This enum type describes the context in which the error occurred, e.g., a connection error, a statement error, etc.

常量 描述
QSqlError::NoError 0 没有出现错误。
QSqlError::ConnectionError 1 Connection error.
QSqlError::StatementError 2 SQL statement syntax error.
QSqlError::TransactionError 3 Transaction failed error.
QSqlError::UnknownError 4 Unknown error.

成员函数文档编制

QSqlError:: QSqlError (const QString & driverText = QString(), const QString & databaseText = QString(), ErrorType type = NoError, int number = -1)

Constructs an error containing the driver error text driverText , the database-specific error text databaseText , the type type and the optional error number number .

QSqlError:: QSqlError (const QSqlError & other )

创建副本为 other .

QSqlError:: ~QSqlError ()

销毁对象并释放任何分配资源。

QString QSqlError:: databaseText () const

Returns the text of the error as reported by the database. This may contain database-specific descriptions; it may be empty.

另请参阅 setDatabaseText (), driverText (),和 text ().

QString QSqlError:: driverText () const

Returns the text of the error as reported by the driver. This may contain database-specific descriptions. It may also be empty.

另请参阅 setDriverText (), databaseText (),和 text ().

bool QSqlError:: isValid () const

Returns true if an error is set, otherwise false.

范例:

QSqlQueryModel model;
model.setQuery("select * from myTable");
if (model.lastError().isValid())
    qDebug() << model.lastError();
					

另请参阅 type ().

int QSqlError:: number () const

Returns the database-specific error number, or -1 if it cannot be determined.

另请参阅 setNumber ().

void QSqlError:: setDatabaseText (const QString & databaseText )

Sets the database error text to the value of databaseText .

另请参阅 databaseText (), setDriverText (),和 text ().

void QSqlError:: setDriverText (const QString & driverText )

Sets the driver error text to the value of driverText .

另请参阅 driverText (), setDatabaseText (),和 text ().

void QSqlError:: setNumber ( int number )

Sets the database-specific error number to number .

另请参阅 number ().

void QSqlError:: setType ( ErrorType type )

Sets the error type to the value of type .

另请参阅 type ().

QString QSqlError:: text () const

This is a convenience function that returns databaseText () 和 driverText () concatenated into a single string.

另请参阅 driverText () 和 databaseText ().

ErrorType QSqlError:: type () const

Returns the error type, or -1 if the type cannot be determined.

另请参阅 setType ().

QSqlError & QSqlError:: operator= (const QSqlError & other )

赋值 other error's values to this error.