我们直接上代码,在注释中来讲解:
#导入需要的包
from flask import Flask
from flask import request
import mysql.connector
conn=mysql.connector.connect(user="root",password="123456",database="Flask_app")#连接数据库,创建Flask_app数据库
cursor=conn.cursor()
app=Flask(__name__)#引入Flask
@app.route('/',methods=['GET','POST'])#首页
def home():
return '<h1>Home</h1>'
@app.route('/signin',methods=['GET'])#登陆界面,请求方式是GET
def signin_form():
return '''<form action="/signin" method="post">
<p><input type="text" name="username"></p>
<p><input type="password" name="password"></p>
<p><button type="submit">Sign In</button></p>
</form>'''
@app.route('/signin',methods=['POST'])#表单提交,请求方式是POST,因为是带有数据提交的
def signin():
cursor.execute('select username from test')#获取Flask_app中test表格的username
username=cursor.fetchall()
print(username)
for u in username:#循环username
if request.form['username']==u[0]:#因为username的形式是[(username1),(username2)]
cursor.execute('select password from test where username=%s',(u[0],))#筛选密码
password=cursor.fetchall()#获取密码
print(password)
if request.form['password']==password[0][0]:#如果匹配的
print("------------------")
return '<h3>Hello,%s</h3>'%u[0]
return '<h3>Bad username or password</h3>'
cursor.close()#关闭
conn.close()
if __name__=='__main__':
app.run()#执行
Flask是一个轻量级的WEB框架,让我们的注意力就从WSGI处理函数转移到URL+对应的处理函数,这样,编写Web App就更加简单了。
用模板的话就是下面的版本:
#导入需要的包
from flask import Flask
from flask import request
from flask import render_template
import mysql.connector
conn=mysql.connector.connect(user="root",password="123456",database="Flask_app")#连接数据库,创建Flask_app数据库
cursor=conn.cursor()
app=Flask(__name__)#引入Flask
@app.route('/',methods=['GET','POST'])#首页
def home():
return render_template('home.html')
@app.route('/signin',methods=['GET'])#登陆界面,请求方式是GET
def signin_form():
return render_template('form.html')
@app.route('/signin',methods=['POST'])#表单提交,请求方式是POST,因为是带有数据提交的
def signin():
cursor.execute('select username from test')#获取Flask_app中test表格的username
username=cursor.fetchall()
print(username)
for u in username:#循环username
if request.form['username']==u[0]:#因为username的形式是[(username1),(username2)]
cursor.execute('select password from test where username=%s',(u[0],))#筛选密码
password=cursor.fetchall()#获取密码
print(password)
if request.form['password']==password[0][0]:#如果匹配的
print("------------------")
return '<h3>Hello,%s</h3>'%u[0]
return '<h3>Bad username or password</h3>'
cursor.close()#关闭
conn.close()
if __name__=='__main__':
app.run()#执行