方法
- len(): 此函数返回字符串中的字符数
- str(): 此函数将传递的参数转换为字符串数据类型
- int(): 此函数将传递的参数转换为整数数据类型
- round(): 此函数将传递的数字舍入到指定的小数位数
实例
- 创建Dialog without Buttonsons模板窗口
- 拖出三个Label部件如图位置,前两Label部件的text属性为Enter First Number,Enter Second Number,第三个Label的text属性为空
- 三个Label部件的objectName属性为labelFirstNumber, labelSecondNumber, labelResult
- 拖出两个Line Edit部件如图位置,设定其object Name属性为lineEditFirstNumber, lineEditSecondNumber
- 拖出四个Push Button部件置于第三个Label上方,设定其text属性为+, -, x, /
- 设定四个Push Button部件的objectName为pushButtonPlus, pushButtonSubtract, pushButtonMultiply,pushButtonDivide
- 保存为demoCalculator.ui文件
- 使用pyuic工具生成demoCalculator.py文件
- 创建callCalculator.py文件,代码如下
import sys
from PyQt5.QtWidgets import QDialog,QApplication
from cookbook_200420.demoCalculator import *
class MyForm(QDialog):
def __init__(self):
super().__init__()
self.ui=Ui_Dialog()
self.ui.setupUi(self)
self.ui.pushButtonPlus.clicked.connect(self.addtwonum)
self.ui.pushButtonSubtract.clicked.connect(self.subtracttwonum)
self.ui.pushButtonMultiply.clicked.connect(self.multiplytwonum)
self.ui.pushButtonDivide.clicked.connect(self.dividetwonum)
self.show()
def addtwonum(self):
a=0
b=0
sum=0
if len(self.ui.lineEditFirstNumber.text())!=0:
a=int(self.ui.lineEditFirstNumber.text())
if len(self.ui.lineEditSecondNumber.text())!=0:
b=int(self.ui.lineEditSecondNumber.text())
sum=a+b
self.ui.labelResult.setText("Addition: " +str(sum))
def subtracttwonum(self):
a=0
b=0
diff=0
if len(self.ui.lineEditFirstNumber.text())!=0:
a=int(self.ui.lineEditFirstNumber.text())
if len(self.ui.lineEditSecondNumber.text())!=0:
b=int(self.ui.lineEditSecondNumber.text())
diff=a-b
self.ui.labelResult.setText("Subtraction: " +str(diff))
def multiplytwonum(self):
a=0
b=0
mult=0
if len(self.ui.lineEditFirstNumber.text())!=0:
a=int(self.ui.lineEditFirstNumber.text())
if len(self.ui.lineEditSecondNumber.text())!=0:
b=int(self.ui.lineEditSecondNumber.text())
mult=a*b
self.ui.labelResult.setText("Multiplication: " +str(mult))
def dividetwonum(self):
a=0
b=0
division=0
if len(self.ui.lineEditFirstNumber.text())!=0:
a=int(self.ui.lineEditFirstNumber.text())
if len(self.ui.lineEditSecondNumber.text())!=0:
b=int(self.ui.lineEditSecondNumber.text())
division=a/b
self.ui.labelResult.setText("Division: " +str(round(division,2)))
if __name__=="__main__":
app=QApplication(sys.argv)
w=MyForm()
w.show()
sys.exit(app.exec())