请求方式
Flask默认是GET请求
如果我们在一个页面中即需要GET请求又需要POST请求那么我们需要重写methods方法:
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="" method="post"> 用户名:<input type="text"> 密码:<input type="password"> <input type="submit" value="登录"> </form> </body> </html>
from flask import Flask,render_template app = Flask(__name__) @app.route('/login',methods=["POST","GET"]) # 重写methods方法 def login(): return render_template("login.html") if __name__ == '__main__': app.run("0.0.0.0",9876)
其他方法
Flask中的request为我们提供了很多属性,只需导入request直接调用对应的属性就可以直接看到效果
request.method
Flask 的 request 中给我们提供了一个 method 属性里面保存的就是前端的请求的方式
from flask import Flask,render_template,request app = Flask(__name__) @app.route('/login',methods=["POST","GET"]) def login(): # 获取前端的请求的方式 print(request.method) return render_template("login.html") if __name__ == '__main__': app.run("0.0.0.0",9876)
request.form
获取请求数据
from flask import Flask,render_template,request app = Flask(__name__) @app.route('/login',methods=["POST","GET"]) def login(): if request.method == "GET": return render_template("login.html") if request.method == "POST": # 获取form表单提交的数据 print(request.form) # ImmutableMultiDict([('username', 'henry'), ('password', '123456')]) return "200 ok" if __name__ == '__main__': app.run("0.0.0.0",9876)
通过reqeust.form属性做登录验证
from flask import Flask,render_template,request app = Flask(__name__) @app.route('/login',methods=["POST","GET"]) def login(): if request.method == "GET": return render_template("login.html") if request.method == "POST": # 获取form表单提交的数据 print(request.form) # ImmutableMultiDict([('username', 'henry'), ('password', '123456')]) username = request.form.get("username") password = request.form.get("password") if username == "henry" and password == "123456": return "200 ok" else: return "404" if __name__ == '__main__': app.run("0.0.0.0",9876)
注意：ImmutableMultiDict类型的数据和我们python中的字典用法是一样的
我们可以通过to_dict()方法将上面的这种数据类型转换成我们python中的字典,如下所示
from flask import Flask,render_template,request app = Flask(__name__) @app.route('/login',methods=["POST","GET"]) def login(): if request.method == "GET": return render_template("login.html") if request.method == "POST": # 获取form表单提交的数据 print(request.form.to_dict()) # {'username': 'henry', 'password': '123456'} username = request.form.get("username") password = request.form.get("password") if username == "henry" and password == "123456": return "200 ok" else: return "404" if __name__ == '__main__': app.run("0.0.0.0",9876)
我们用get方法取字典中的值防止报错
request.headers
获取请求头中的数据
print(request.headers)
#Host: 192.168.16.42:9876 #Connection: keep-alive #Content-Length: 27 #Cache-Control: max-age=0 #Origin: http://192.168.16.42:9876 #Upgrade-Insecure-Requests: 1 #Content-Type: application/x-www-form-urlencoded #User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.100 Safari/537.36 #Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3 #Referer: http://192.168.16.42:9876/login #Accept-Encoding: gzip, deflate #Accept-Language: zh-CN,zh;q=0.9
request.args
获取GET请求中的url参数
print(request.args) # ImmutableMultiDict([('name', 'henry'), ('age', '18')]) # 通过to_dict()方法转换成字典 print(request.args.to_dict()) # {'name': 'henry', 'age': '18'}
request.files
上传文件
前端页面
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <form action="" method="post" enctype="multipart/form-data"> 用户名:<input type="text" name="username"> 密码:<input type="password" name="password"> <input type="file" name="my_file"> <input type="submit" value="登录"> </form> </body> </html>
后端代码
from flask import Flask,render_template,request app = Flask(__name__) @app.route('/login',methods=["POST","GET"]) def login(): if request.method == "GET": return render_template("login.html") if request.method == "POST": username = request.form.get("username") password = request.form.get("password") if username == "henry" and password == "123456": print(request.files) # ImmutableMultiDict([('my_file', <FileStorage: 'click点击事件.gif' ('image/gif')>)]) files = request.files.get("my_file") # files是FileStorage类型 注意:不是文件句柄 print(files.filename) # click点击事件.gif 【文件名字】 files.save(files.filename) # FileStorage类型调用save方法保存 return "200 ok" else: return "404" if __name__ == '__main__': app.run("0.0.0.0",9876)
fp = os.path.join("templates",files.filename) # 通过os模块指定保存路径
request中的其他属性
print(request.url) # 获取访问全路径 print(request.path) # 路由地址 /login print(request.values) # 可以获取URL中的参数 也可以获取 FormData中的数据 print(request.args.get("id")) # 获取URL中的参数 print(request.args["id"]) # 获取URL中的参数 print(request.args.to_dict()) # 获取URL中的参数 转换成 字典 print(request.environ) # 获取请求原始信息 print(request.base_url) # 获取URL头,不包含参数
两个特殊的属性
print(request.json) # 请求头中 Content-type:application/json 数据序列化 request.json print(request.data) # 请求头中 Content-type 不包含 Form or data