环境：
Python2.7+MySQL5.6+PyQt4
简单的图形化界面操作数据库：模仿写一个类似于navicat完毕可视化检索功能的界面，利用PyQt可视化编程高速完毕界面设计，这点比Tkinter设计要简单；
1.利用PyQt进行界面设计：
打开PyQt，新建，选择Main Window，选择左端的控件拖动完毕界面的设计，选中元素。能够从右側查看元素的信息以及改动其属性值，以下贴上设计图：
在设计界面中选中元素双击。能够改动其属性名。加入text。改变显示字符格式等；
2.设计完毕后，保存为.ui文件。接下来将其转换为.py文件：
打开cmd：进入PyQt安装文件夹：
Libsite-packagesPyQt4uic>
键入命令格式：
python pyuic.py -o .py文件文件夹+文件名称 .ui文件文件夹+文件名称
我保存的.ui文件放在D盘根文件夹中，生成的.py文件命名为nihao0.py
3.打开Python执行.py，查看界面
在原有的代码基础上加入下列代码：
import sys
class MyWindow(QtGui.QMainWindow,Ui_MainWindow):#PyQt生产的是一个叫做Ui_MainWindow的类，仅仅须要放在一个框架下画出来就可以。
def __init__(self):
super(MyWindow,self).__init__()
self.setupUi(self)
if __name__=="__main__":
app=QtGui.QApplication(sys.argv)#建立一个app，把框架放在这个app中执行
app.aboutToQuit.connect(app.deleteLater)
myshow=MyWindow()
myshow.show()
sys.exit(app.exec_())#也能够写成app.exec_() sys.exit(0)，前者是循环整个界面，后者是退出app执行结果：
这时我们得到了一个我们想得到的界面。仅仅须要往这个界面中加入各种事件就可以；
4.动态生成SQL语句——准备
新建数据库mysql。和表格students,表格的属性为
DDL为：
CREATE TABLE `students` ( `Sid` char(10) NOT NULL, `Sname` char(10) DEFAULT NULL, `Sage` int(3) DEFAULT NULL, `Ssex` char(4) DEFAULT NULL, `Sclass` char(7) DEFAULT NULL, `Sdept` char(10) DEFAULT NULL, `Saddr` char(40) DEFAULT NULL, PRIMARY KEY (`Sid`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;先写好句柄：
sqlsting="select * from students where "然后写一个clicked()事件。点击查询的时候，依据用户输入动态构造SQL语句
使用到的方法主要有：
是否选择复选框：checked()
读入输入：text()
5.动态生成SQL语句——字符串构造
构造技巧：
是否须要加and：假设前面已经有了原子公式，须要添加and，否则不加。使用一个flag就可以；
是否须要加引號：字符型须要加引號，数字不须要加。
数字类型须要先转换为字符类型：当为数字类型转换为字符型str()。推断数据类型type()，事实上能够不写，由于从界面返回的都是QtString类型的数据。
推断什么时候使用Like(字符串匹配问题%)：字符串方法.find("%")。返回值是第一个%出现的位置，假设%不存在。则返回-1；
6.界面显示问题
self.sql_out = QtGui.QTextBrowser(self.centralwidget)：显示框用法：
.setText(str)：清除原来数据。显示新的字符串
.append(str)：在末尾加入新的字符串
self.result_out = QtGui.QTableWidget(self.centralwidget)：表格框用法：
.setItem(i,j,newItem)：将newItem放在第i行，第j列。注意ij都从0開始；
newItem的声明格式为newItem = QtGui.QTableWidgetItem(str)，即在(i,j)位置显示str
注意QTableWidget仅仅能显示字符串，不能显示数字，全部在显示数据前，须要推断是否为数字：
解决方法：type()以及str()
7.数据库连接问题：
具体在Python&MySQL中已经讲述清除，能够作參考
8.贴上Python代码及执行结果：
# -*- coding: utf-8 -*-
# Form implementation generated from reading ui file 'D:/nihao.ui'
#
# Created: Fri Apr 01 15:28:59 2016
# by: PyQt4 UI code generator 4.11.3
#
# WARNING! All changes made in this file will be lost!
from PyQt4 import QtCore, QtGui
import sys
import MySQLdb
try:
_fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
def _fromUtf8(s):
return s
try:
_encoding = QtGui.QApplication.UnicodeUTF8
def _translate(context, text, disambig):
return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
def _translate(context, text, disambig):
return QtGui.QApplication.translate(context, text, disambig)
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
self.conn=MySQLdb.connect(
host='localhost',
user='root',
passwd='',
db='mysql',
#
charset='utf8',
)
self.cur=self.conn.cursor()
self.sqlstring="select * from students where "
MainWindow.setObjectName(_fromUtf8("MainWindow"))
MainWindow.resize(760, 440)
self.centralwidget = QtGui.QWidget(MainWindow)
self.centralwidget.setObjectName(_fromUtf8("centralwidget"))
self.frame = QtGui.QFrame(self.centralwidget)
self.frame.setGeometry(QtCore.QRect(10, 10, 491, 121))
self.frame.setFrameShape(QtGui.QFrame.StyledPanel)
self.frame.setFrameShadow(QtGui.QFrame.Raised)
self.frame.setObjectName(_fromUtf8("frame"))
self.check_Sid = QtGui.QCheckBox(self.frame)
self.check_Sid.setGeometry(QtCore.QRect(20, 10, 71, 16))
self.check_Sid.setObjectName(_fromUtf8("check_Sid"))
self.check_Sage = QtGui.QCheckBox(self.frame)
self.check_Sage.setGeometry(QtCore.QRect(20, 70, 71, 16))
self.check_Sage.setObjectName(_fromUtf8("check_Sage"))
self.check_Sname = QtGui.QCheckBox(self.frame)
self.check_Sname.setGeometry(QtCore.QRect(20, 40, 71, 16))
self.check_Sname.setObjectName(_fromUtf8("check_Sname"))
self.check_Ssex = QtGui.QCheckBox(self.frame)
self.check_Ssex.setGeometry(QtCore.QRect(20, 100, 71, 16))
self.check_Ssex.setObjectName(_fromUtf8("check_Ssex"))
self.Sid = QtGui.QLineEdit(self.frame)
self.Sid.setGeometry(QtCore.QRect(90, 10, 113, 16))
self.Sid.setObjectName(_fromUtf8("Sid"))
self.Sname = QtGui.QLineEdit(self.frame)
self.Sname.setGeometry(QtCore.QRect(90, 40, 113, 16))
self.Sname.setObjectName(_fromUtf8("Sname"))
self.first_Sage = QtGui.QLineEdit(self.frame)
self.first_Sage.setGeometry(QtCore.QRect(90, 70, 41, 16))
self.first_Sage.setObjectName(_fromUtf8("first_Sage"))
self.Ssex = QtGui.QLineEdit(self.frame)
self.Ssex.setGeometry(QtCore.QRect(90, 100, 113, 16))
self.Ssex.setObjectName(_fromUtf8("Ssex"))
self.label = QtGui.QLabel(self.frame)
self.label.setGeometry(QtCore.QRect(140, 70, 16, 16))
self.label.setObjectName(_fromUtf8("label"))
self.last_Sage = QtGui.QLineEdit(self.frame)
self.last_Sage.setGeometry(QtCore.QRect(160, 70, 41, 16))
self.last_Sage.setObjectName(_fromUtf8("last_Sage"))
self.check_Sdept = QtGui.QCheckBox(self.frame)
self.check_Sdept.setGeometry(QtCore.QRect(270, 40, 71, 16))
self.check_Sdept.setObjectName(_fromUtf8("check_Sdept"))
self.Sdept = QtGui.QLineEdit(self.frame)
self.Sdept.setGeometry(QtCore.QRect(340, 40, 113, 16))
self.Sdept.setObjectName(_fromUtf8("Sdept"))
self.Sclass = QtGui.QLineEdit(self.frame)
self.Sclass.setGeometry(QtCore.QRect(340, 10, 113, 16))
self.Sclass.setObjectName(_fromUtf8("Sclass"))
self.check_Sclass = QtGui.QCheckBox(self.frame)
self.check_Sclass.setGeometry(QtCore.QRect(270, 10, 71, 16))
self.check_Sclass.setObjectName(_fromUtf8("check_Sclass"))
self.Saddr = QtGui.QLineEdit(self.frame)
self.Saddr.setGeometry(QtCore.QRect(340, 70, 113, 16))
self.Saddr.setObjectName(_fromUtf8("Saddr"))
self.check_Saddr = QtGui.QCheckBox(self.frame)
self.check_Saddr.setGeometry(QtCore.QRect(270, 70, 71, 16))
self.check_Saddr.setObjectName(_fromUtf8("check_Saddr"))
self.find = QtGui.QPushButton(self.frame)
self.find.setGeometry(QtCore.QRect(380, 100, 75, 21))
self.find.setObjectName(_fromUtf8("find"))
self.sql_out = QtGui.QTextBrowser(self.centralwidget)
self.sql_out.setGeometry(QtCore.QRect(10, 140, 740, 61))
self.sql_out.setObjectName(_fromUtf8("sql_out"))
self.result_out = QtGui.QTableWidget(self.centralwidget)
self.result_out.setEditTriggers(QtGui.QAbstractItemView.NoEditTriggers)#不可编辑表格
self.result_out.setGeometry(QtCore.QRect(10, 210, 740, 171))
self.result_out.setObjectName(_fromUtf8("result_out"))
self.result_out.setColumnCount(7)
self.result_out.setRowCount(10)
self.result_out.resizeColumnsToContents()
self.result_out.resizeRowsToContents()
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(0, item)
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(1, item)
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(2, item)
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(3, item)
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(4, item)
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(5, item)
item = QtGui.QTableWidgetItem()
self.result_out.setHorizontalHeaderItem(6, item)
self.result_out.horizontalHeader().setDefaultSectionSize(100)
self.result_out.horizontalHeader().setMinimumSectionSize(25)
self.result_out.verticalHeader().setDefaultSectionSize(30)
self.pushButton_2 = QtGui.QPushButton(self.centralwidget)
self.pushButton_2.setGeometry(QtCore.QRect(675, 390, 75, 21))
self.pushButton_2.setObjectName(_fromUtf8("pushButton_2"))
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtGui.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 509, 23))
self.menubar.setObjectName(_fromUtf8("menubar"))
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtGui.QStatusBar(MainWindow)
self.statusbar.setObjectName(_fromUtf8("statusbar"))
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow", None))
self.check_Sid.setText(_translate("MainWindow", "学号", None))
self.check_Sage.setText(_translate("MainWindow", "年龄自", None))
self.check_Sname.setText(_translate("MainWindow", "姓名", None))
self.check_Ssex.setText(_translate("MainWindow", "性别", None))
self.label.setText(_translate("MainWindow", "到", None))
self.check_Sdept.setText(_translate("MainWindow", "系", None))
self.check_Sclass.setText(_translate("MainWindow", "班级", None))
self.check_Saddr.setText(_translate("MainWindow", "地址", None))
self.find.setText(_translate("MainWindow", "查询", None))
self.sql_out.setText(self.sqlstring)
item = self.result_out.horizontalHeaderItem(0)
item.setText(_translate("MainWindow", "Sid", None))
item = self.result_out.horizontalHeaderItem(1)
item.setText(_translate("MainWindow", "Sname ", None))
item = self.result_out.horizontalHeaderItem(2)
item.setText(_translate("MainWindow", "Sage", None))
item = self.result_out.horizontalHeaderItem(3)
item.setText(_translate("MainWindow", "Ssex", None))
item = self.result_out.horizontalHeaderItem(4)
item.setText(_translate("MainWindow", "Sclass", None))
item = self.result_out.horizontalHeaderItem(5)
item.setText(_translate("MainWindow", "Sdept", None))
item = self.result_out.horizontalHeaderItem(6)
item.setText(_translate("MainWindow", "Saddr", None))
self.pushButton_2.setText(_translate("MainWindow", "退出", None))
def mousePressEvent(self,event):
if event.self.find()==QtCore.Qt.LeftButton:
print "nihao"
def buttonTest(self):
temp_sqlstring=self.sqlstring
is_first = True
if self.check_Sid.isChecked():
mystr = self.Sid.text()
if is_first:
is_first = False
if mystr.find("%")==-1:
temp_sqlstring += "Sid = '" + self.Sid.text() + "'"
else:
temp_sqlstring += "Sid like '" + self.Sid.text() + "'"
else:
if mystr.find("%")==-1:
temp_sqlstring += " and Sid = '" + self.Sid.text() + "'"
else:
temp_sqlstring += " and Sid like '" + self.Sid.text() + "'"
if self.check_Sname.isChecked():
if is_first:
mystr =self.Sname.text()
is_first = False
if mystr.find("%")==-1:
temp_sqlstring += "Sname = '" + self.Sname.text() + "'"
else:
temp_sqlstring += "Sname like '" + self.Sname.text() + "'"
else:
if mystr.find("%")==-1:
temp_sqlstring += " and Sname = '" + self.Sname.text() + "'"
else:
temp_sqlstring += " and Sname like '" + self.Sname.text() + "'"
if self.check_Sage.isChecked():
if is_first:
is_first = False
temp_sqlstring += "Sage >= " + self.first_Sage.text() +
" and Sage <= " + self.last_Sage.text()
else:
temp_sqlstring += " and Sage >= " + self.first_Sage.text() +
" and Sage <= " + self.last_Sage.text()
if self.check_Ssex.isChecked():
if is_first:
is_first = False
temp_sqlstring += "Ssex = '" + self.Ssex.text() + "'"
else:
temp_sqlstring += " and Ssex = '" + self.Ssex.text() + "'"
if self.check_Sclass.isChecked():
if is_first:
mystr = self.Sclass.text()
is_first = False
if mystr.find("%")==-1:
temp_sqlstring += "Sclass = '" + self.Sclass.text() + "'"
else:
temp_sqlstring += "Sclass like '" + self.Sclass.text() + "'"
else:
if mystr.find("%")==-1:
temp_sqlstring += " and Sclass = '" + self.Sclass.text() + "'"
else:
temp_sqlstring += " and Sclass like '" + self.Sclass.text() + "'"
if self.check_Sdept.isChecked():
if is_first:
mystr = self.Sdept.text()
is_first = False
if mystr.find("%")==-1:
temp_sqlstring += "Sdept = '" + self.Sdept.text() + "'"
else:
temp_sqlstring += "Sdept like '" + self.Sdept.text() + "'"
else:
if mystr.find("%")==-1:
temp_sqlstring += " and Sdept = '" + self.Sdept.text() + "'"
else:
temp_sqlstring += " and Sdept like '" + self.Sdept.text() + "'"
if self.check_Saddr.isChecked():
if is_first:
mystr = self.Saddr.text()
is_first = False
if mystr.find("%")==-1:
temp_sqlstring += "Saddr = '" + self.Saddr.text() + "'"
else:
temp_sqlstring +=" and Saddr like '" + self.Saddr.text() + "'"
else:
if mystr.find("%")==-1:
temp_sqlstring += " and Saddr = '" + self.Saddr.text() + "'"
else:
temp_sqlstring +=" and Saddr like '" + self.Saddr.text() + "'"
self.result_out.clearContents()#每一次查询时清除表格中信息
if not(is_first):
self.cur.execute(temp_sqlstring)
k=0
for i in self.cur:
w=0
for j in i:
if type(j)==long:
newItem = QtGui.QTableWidgetItem(str(j))
else:
newItem = QtGui.QTableWidgetItem(j)
self.result_out.setItem(k,w,newItem)
w += 1
k +=1
self.sql_out.setText("")
self.sql_out.append(temp_sqlstring)
print "find button pressed"
def buttonExit(self):
self.conn.commit()
self.cur.close()
self.conn.close()
self.close()
def keyPressEvent(self, e):
if e.key() == QtCore.Qt.Key_Escape:
self.buttonExit()
class MyWindow(QtGui.QMainWindow,Ui_MainWindow):
def __init__(self):
super(MyWindow,self).__init__()
self.setupUi(self)
self.connect(self.find, QtCore.SIGNAL('clicked()'), self.buttonTest)
self.connect(self.pushButton_2,QtCore.SIGNAL('clicked()'),self.buttonExit)
if __name__=="__main__":
app=QtGui.QApplication(sys.argv)
app.aboutToQuit.connect(app.deleteLater)
myshow=MyWindow()
myshow.show()
sys.exit(app.exec_())
#app.exec_()
#sys.exit(0)注：执行前首先确保已经在MySQL中存在mysql数据库以及students表格。执行结果：
因为原来设计的界面比較小。后来改变了各个控件的长宽；
这样就完毕的简单的界面化动态构造SQL语句，并将结果返回界面显示功能。