【python&flask-1】简单实现加减乘除输入界面

app.py

import flask
from flask import Flask, render_template, request
# 计算精确的浮点结果，float加法也计算不出来
from decimal import Decimal

app = Flask(__name__)

@app.route('/')
def home():
    return render_template('index.html')

@app.route('/calculate', methods=['POST'])
# POST请求处理用户提交的数据
def calculate():
    num1 = Decimal(request.form['num1'])
    num2 = Decimal(request.form['num2'])
    operation = request.form['operation']
    result = Decimal(0)
    # 输入的两个数和运算符，结果初始为0

    if operation == 'add':
        result = num1 + num2
        # 加
    elif operation == 'subtract':
        result = num1 - num2
        # 减
    elif operation == 'multiply':
        result = num1 * num2
        # 乘
    elif operation == 'divide':
        if num2 != Decimal(0):
            result = num1 / num2
        else:
            return "错误:分母不能为0"
        # 除
    result = round(result,4)
    # 保留四位小数

    return render_template('result.html', num1=num1, num2=num2, operation=operation, result=result)
    # 然后将计算结果和输入的两个参数返回给result.html渲染
if __name__ == '__main__':
    app.run(debug=True)

templates文件夹

index.html

    


    
在线计算器
    

        
        
        
            +
            -
            *
            /
            
        
        
        开始计算
        
    

result.html

    


    
计算结果
    
{{ num1 }} {{ operation }} {{ num2 }} = {{ result }}
    

实现效果

支持小数点计算