flask的重定向(redirect)传递参数的方法

flask中的重定向redirect方法经常被用来跳转页面,那redirect在跳转页面的同时能不能传递咱们下一个页面须要的参数呢?html

带着这个问题我看了redirect()的源码,以下:python

 1 def redirect(location, code=302, Response=None):  2     """Returns a response object (a WSGI application) that, if called,  3  redirects the client to the target location. Supported codes are 301,  4  302, 303, 305, and 307. 300 is not supported because it's not a real  5  redirect and 304 because it's the answer for a request with a request  6  with defined If-Modified-Since headers.  7 
 8  .. versionadded:: 0.6  9  The location can now be a unicode string that is encoded using 10  the :func:`iri_to_uri` function. 11 
12  .. versionadded:: 0.10 13  The class used for the Response object can now be passed in. 14 
15  :param location: the location the response should redirect to. 16  :param code: the redirect status code. defaults to 302. 17  :param class Response: a Response class to use when instantiating a 18  response. The default is :class:`werkzeug.wrappers.Response` if 19  unspecified. 20     """
21     if Response is None: 22         from werkzeug.wrappers import Response 23 
24     display_location = escape(location) 25     if isinstance(location, text_type): 26         # Safe conversion is necessary here as we might redirect
27         # to a broken URI scheme (for instance itms-services).
28         from werkzeug.urls import iri_to_uri 29         location = iri_to_uri(location, safe_conversion=True) 30     response = Response( 31         '<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">\n'
32         '<title>Redirecting...</title>\n'
33         '<h1>Redirecting...</h1>\n'
34         '<p>You should be redirected automatically to target URL: '
35         '<a href="%s">%s</a>. If not click the link.' %
36         (escape(location), display_location), code, mimetype='text/html') 37     response.headers['Location'] = location 38     return response

源码的解释很清楚,redirect就是一个响应,它总共有三个参数,这三个参数都是用来实例化响应的.flask

第一个参数:location是响应应该重定向到的位置。第二个参数code是重定向状态代码,,最后一个参数是实例化响应时要使用的响应类.app

因此说redirect自己是不能像render_template那样来传递参数的.url

可是!!spa

若是你要传递的参数只是像string,int这样的数据,你能够用url_for来做为location参数,而url_for是能够作到传递这些简单数据的.code

redirect(url_for())传递参数的方法以下:htm

@app.route('/login/',methods=['GET','POST'])
def user_login():
    username = 'unsprint'
    return redirect(url_for('index',username=username))  #url_for在index的路由和username之间加一个?进行拼接,使得username成为一个可接受的参数
 
#经过路由接收参数                 
@app.route('/index/?<string:username>')  #这里指定了接收的username的类型,若是不符合会报错,
def index(username):                     #能够将string改为path, 这样username就会被当成路径来接收,也就是说username能够是任意可键入路由的值了

return username