1 新建一个项目：
Database01.pro
SOURCES += \
main.cpp \
Contact.cpp
QT += gui widgets sql
CONFIG += C++11
HEADERS += \
Contact.h
Contact.h
#ifndef CONTACT_H
#define CONTACT_H
#include <QWidget>
#include <QSqlTableModel>
#include <QTableView>
#include <QLineEdit>
#include <QPushButton>
class Contact : public QWidget
{
Q_OBJECT
public:
explicit Contact(QWidget *parent = 0);
QSqlTableModel* _model;
QTableView* _view;
QLineEdit* _filter;
QPushButton* _add;
QPushButton* _del;
QPushButton* _reset;
QPushButton* _submit;
signals:
public slots:
void slotModelDataChanged(QModelIndex,QModelIndex);
void slotFilterChanged(QString filter);
};
#endif // CONTACT_H
Contact.cpp
#include "Contact.h"
#include <QVBoxLayout>
#include <QHBoxLayout>
#include <QSqlRecord>
#include <QCompleter>
#include <QDebug>
Contact::Contact(QWidget *parent) :
QWidget(parent)
{
//创建一个QSqlTableModel
_model = new QSqlTableModel;
//创建QTable
_view = new QTableView;
//view里面设置model
_view->setModel(_model);
_model->setTable("tcontact");
//手动提交
_model->setEditStrategy(QSqlTableModel::OnManualSubmit);
connect(_model, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
this, SLOT(slotModelDataChanged(QModelIndex,QModelIndex)));
_model->select();
// set Layout
QVBoxLayout* vBox = new QVBoxLayout(this);
vBox->addWidget(_view);
QHBoxLayout* hBox = new QHBoxLayout;
vBox->addLayout(hBox);
//添加add
hBox->addWidget(_filter = new QLineEdit, 1);
hBox->addWidget(_add=new QPushButton("Add"));
hBox->addWidget(_del=new QPushButton("Del"));
hBox->addWidget(_reset=new QPushButton("Reset"));
hBox->addWidget(_submit=new QPushButton("Submit"));
connect(_add, &QPushButton::clicked, [&](){
QSqlRecord record = _model->record();
_model->insertRecord(-1, record);
});
connect(_del, &QPushButton::clicked, [&](){});
connect(_reset, &QPushButton::clicked, [&](){});
connect(_submit, &QPushButton::clicked, [&](){
_model->submitAll();
});
//模糊查询
connect(_filter, SIGNAL(textChanged(QString)),
this, SLOT(slotFilterChanged(QString)));
slotModelDataChanged(QModelIndex(), QModelIndex());
}
void Contact::slotFilterChanged(QString filter)
{
if(filter.isEmpty())
{
_model->setFilter("");
_model->select();
return;
}
// username like filter or password like filter .......
QSqlRecord record = _model->record();
QString modelFilter;
for(int i=0; i<record.count(); ++i)
{
if(i!=0)
{
modelFilter += " or ";
}
QString field = record.fieldName(i);
QString subFilter = QString().sprintf("%s like '%%%s%%'", field.toUtf8().data(), filter.toUtf8().data());
// qDebug() << subFilter;
modelFilter += subFilter;
}
qDebug() << modelFilter;
_model->setFilter(modelFilter);
_model->select();
}
void Contact::slotModelDataChanged(QModelIndex,QModelIndex)
{
QStringList strList;
for(int i=0; i<_model->rowCount(); ++i)
{
QSqlRecord record = _model->record(i);
for(int j=0; j<record.count(); ++j)
{
QVariant var = record.value(j);
if(var.isNull()) continue;
strList << var.toString();
}
}
qDebug() << strList;
QCompleter* completer=new QCompleter(strList);
_filter->setCompleter(completer);
}
main.cpp
#include <QApplication>
#include "Widget05.h"
#include <QSqlDatabase>
#include <QSqlError>
#include <QDebug>
#include "Contact.h"
int main(int argc,char* argv[])
{
QApplication app(argc,argv);
/*QT可以操作 QSLITE QODBC,QPLSQL 这些数据库*/
//下面表示使用mysql数据库，因为这里的db没有用到db，所以可以把它放在main中
//本质：在QT里面打开一个数据库之后，就会保存一个数据库连接，
//其它的位置就可以任意使用这个全局的变量了
QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
db.setHostName("127.0.0.1"); //设置数据库所在位置
db.setUserName("root"); //设置数据库的用户名
db.setPassword("123456"); //设置数据库的密码
db.setDatabaseName("d0718"); //设置数据库名称
bool bRet = db.open(); //打开数据库连接
if(bRet == false)
{
//说明可以通过db.lastError()的方式得到错误信息
qDebug() << "error open database" << db.lastError().text();
exit(0);
}
qDebug() << "open database success";
//注意Widget02要写在上面代码的下面
Contact c;
c.show();
return app.exec();
}
运行结果：
