Flask安装与使用

Flask是一个使用Python编写的轻量级Web应用框架。

Flask安装：

1、pip install Flask

2、以上命令安装报错时，可使用如下地址安装：pip install Flask -i http://pypi.doubanio.com/simple/ --trusted-host pypi.doubanio.com  //豆瓣镜像

引入不报错，说明安装成功

 3、使用flask开发get接口

from flask import Flask,request

app = Flask(__name__)

@app.route("/")
def hello_world():
    return "hello world"

@app.route("/hello")
def hello_world2():
    return "hello world222"

@app.route("/hello/<username>")
def hello_world3(username):
    print(username)
    return "hello world333" + username

@app.route("/hello/args/<username>")
def hello_world4(username):
    print(username)
    key = request.args.get("key")
    value = request.args.get("value")
    print(key)
    print(value)
    return "hello world444" + username + "::" + key + "::" + value

if __name__ == "__main__":
    app.run()

 

 4、使用flask开发post接口

from flask import Flask,request

app = Flask(__name__)

@app.route("/mypost", methods=["post"])
def my_post():
    return "post request"

@app.route("/mypost1", methods=["post"])
def my_post1():
    #表单数据类型
    username = request.form["username"]
    print(username)
    sex = request.form["sex"]
    print(sex)
    return "post request" + username + ":" + sex

@app.route("/mypost2", methods=["post"])
def my_post2():
    #json数据格式
    request_data = request.get_json()
    print(request_data)
    print(request_data["user"])
    return "post request" + str(request_data)

if  __name__ == "__main__":
    app.run(port=5555)

 

 5、访问mysql数据库

import pymysql
from flask import Flask

#连接信息
conn = pymysql.connect(
    host = "localhost",
    user = "root",
    password = "root",
    database = "trip_django",
    charset = "utf8"
)

cursor = conn.cursor()

app = Flask(__name__)

@app.route("/")
def hello_world():
    sql = "select * from account_user"
    result = cursor.execute(sql)
    #得到查询后的真正结果
    r = cursor.fetchall()
    print(r)
    return str(r)

if __name__ == "__main__":
    app.run()