转 Qt QSqlTableModel 使用心得

Qt QSqlTableModel 使用心得

连接数据库

执行sql查询，条件显示，排序

获取记录数，列数以及记录内容，字段内容

新增，修改，删除，恢复

其它

1---------------连接数据库（我用的access2003做实验）

在.pro文件添加

QT +=SQL

win32:CONFIG+=console

------------------------MAIN.CPP---------------

#include <QtGui/QApplication>

#include <QSqlDatabase>

#include <QSqlQuery>

#include <QDebug>

#include <QVariant>

#include <QString>

#include <QSqlTableModel>

#include <QTableView>

#include "mainwindow.h"

int main(intargc, char *argv[])

{

QApplication a(argc, argv);

// MainWindow w;

//w.show();

QSqlDatabase db = QSqlDatabase::addDatabase("QODBC");

db.setDatabaseName("DRIVER={Microsoft AccessDriver (*.mdb)};FIL={MS Access};DBQ=barcode.mdb;UID='';PWD=''");

bool ok = db.open();

if(ok)

{

qDebug()<<"connect ok!";

}

else

{

qDebug()<<"connect error!";

return false;

}

return a.exec();

}

2-----执行sql查询，条件显示，排序

查询：

model = newQSqlTableModel(this);
model->setTable(“student”);
model->setEditStrategy(QSqlTableModel::OnManualSubmit);
model->select(); //选取整个表的所有行
// model->removeColumn(1); //不显示第二列,如果这时添加记录，则该属性的值添加不上

QTableView *view= new QTableView;

view->setModel(model);

view->show();

//View->setEditTriggers(QAbstractItemView::NoEditTriggers); 使其不可编辑

条件：（等价于SQL语句的where）

model->setFilter(QObject::tr(“name= ‘admin’”).arg(name)); //根据姓名进行筛选
model->select(); //显示结果

排序:(等价于ORDERBY)
model->setSort(0,Qt::AscendingOrder); //id属性，即第0列，升序排列
model->select();

model->setSort(0,Qt::DescendingOrder); //id属性，即第0列，降序排
model->select();

3------获取记录数，列数以及记录内容，字段内容

记录数： Model->rowcount

记录值：

值=model.record(num).value(1).toString();

Qrecord record= QSqlRecord record = tablemodel.record(记录行数);

值=Record.value(“字段名或索引”)

字段数：

字段值：

4------新增，修改，删除,提交，撤销

新增：

    int rowNum = model->rowCount();//获得表的行数
   int id = 10;
    model->insertRow(rowNum); //添加一行
    model->setData(model->index(rowNum,0),id);
    //model->submitAll(); //可以直接提交

或者用record添加

QSqlRecord record = tablemodel.record();

record.setValue("nam","new");

model.insertRecord(1,record);

修改：

首先用条件找到某一条记录

QSqlRecord record = tablemodel.record(num);

record.setValue("name",record.value("name").toString()+"2");

tablemodel.setRecord(num,record);

if(tablemodel.submitAll())

"成功！"

else

"失败！"

或者用下面方法用setData()来修改，代码如下：
model.setData(model.index(1,1),"new");
if(tablemodel.submitAll())
"成功！"
else
"失败！"

删除：
    int curRow = ui->tableView->currentIndex().row();
    //获取选中的行
    model->removeRow(curRow);
    //删除该行
    int ok = QMessageBox::warning(this,tr(“删除当前行!”),tr(“你确定”
                                                          “删除当前行吗？”),
                        QMessageBox::Yes,QMessageBox::No);
    if(ok == QMessageBox::No)
    {
       model->revertAll();//如果不删除，则撤销
    }
    else model->submitAll(); //否则提交，在数据库中删除该行

如果没有table

tablemodel.removeRows(起始行, 要删除的总行数);
model.submitAll();

提交

    model->database().transaction();//开始事务操作
    if (model->submitAll()) {
        model->database().commit();//提交
    } else {
        model->database().rollback();//回滚
        QMessageBox::warning(this,tr(“tableModel”),
                            tr(“数据库错误: %1″)
                            .arg(model->lastError().text()));
    }

撤销

model->revertAll();

5------其它

he QSqlTableModel class provides an editable data model for a single database table. More...

[cpp] view plain copy print ?

<span class="preprocessor" style="color:#404040">#include <QSqlTableModel></span>

Inherits: QSqlQueryModel.

Inherited by: QSqlRelationalTableModel.

List of all members, including inherited members

Public Types

enum	EditStrategy { OnFieldChange, OnRowChange, OnManualSubmit }

Public Functions

	QSqlTableModel ( QObject * parent = 0, QSqlDatabase db = QSqlDatabase() )
virtual	~QSqlTableModel ()
QSqlDatabase	database () const
EditStrategy	editStrategy () const
int	fieldIndex ( const QString & fieldName ) const
QString	filter () const
bool	insertRecord ( int row, const QSqlRecord & record )
bool	isDirty ( const QModelIndex & index ) const
QSqlIndex	primaryKey () const
virtual void	revertRow ( int row )
virtual bool	select ()
virtual void	setEditStrategy ( EditStrategy strategy )
virtual void	setFilter ( const QString & filter )
bool	setRecord ( int row, const QSqlRecord & record )
virtual void	setSort ( int column, Qt::SortOrder order )
virtual void	setTable ( const QString & tableName )
QString	tableName () const

Reimplemented Public Functions

virtual void	clear ()
virtual QVariant	data ( const QModelIndex & index, int role = Qt::DisplayRole ) const
virtual Qt::ItemFlags	flags ( const QModelIndex & index ) const
virtual QVariant	headerData ( int section, Qt::Orientation orientation, int role = Qt::DisplayRole ) const
virtual bool	insertRows ( int row, int count, const QModelIndex & parent = QModelIndex() )
virtual bool	removeColumns ( int column, int count, const QModelIndex & parent = QModelIndex() )
virtual bool	removeRows ( int row, int count, const QModelIndex & parent = QModelIndex() )
virtual int	rowCount ( const QModelIndex & parent = QModelIndex() ) const
virtual bool	setData ( const QModelIndex & index, const QVariant & value, int role = Qt::EditRole )
virtual void	sort ( int column, Qt::SortOrder order )

16 public functions inherited from QSqlQueryModel
2 public functions inherited from QAbstractTableModel
35 public functions inherited from QAbstractItemModel
29 public functions inherited from QObject

Public Slots

virtual void	revert ()
void	revertAll ()
virtual bool	submit ()
bool	submitAll ()

2 public slots inherited from QAbstractItemModel
1 public slot inherited from QObject

Signals

void	beforeDelete ( int row )
void	beforeInsert ( QSqlRecord & record )
void	beforeUpdate ( int row, QSqlRecord & record )
void	primeInsert ( int row, QSqlRecord & record )

18 signals inherited from QAbstractItemModel
1 signal inherited from QObject

Protected Functions

virtual bool	deleteRowFromTable ( int row )
QModelIndex	indexInQuery ( const QModelIndex & item ) const
virtual bool	insertRowIntoTable ( const QSqlRecord & values )
virtual QString	orderByClause () const
virtual QString	selectStatement () const
void	setPrimaryKey ( const QSqlIndex & key )
void	setQuery ( const QSqlQuery & query )
virtual bool	updateRowInTable ( int row, const QSqlRecord & values )