from flask import Flask, redirect, render_template, request, url_for from werkzeug.utils import secure_filename import os app = Flask(__name__) ALLOWED_EXTENSIONS = set(['txt', 'pdf', 'png', 'jpg', 'jpeg', 'gif', 'doc']) # 设置允许上传的文件的类型 def allowed_file(filename):     """     上传的文件类型     :param filename: 传入的文件名     :return: 返回True 或者 False     """     return "." in filename and filename.rsplit(".", 1)[1] in ALLOWED_EXTENSIONS @app.route("/", methods=["GET", "POST"]) def file_name():     """     上传文件     :return: 返回上传文件的url地址     """     if request.method == "POST":         f = request.files["file"]         if f and allowed_file(f.filename):             path = os.path.split(os.getcwd())[0]             print(path)             file = path+"/demo/templates/"+secure_filename(f.filename)             print(file)             f.save(file)             return redirect("/uploads")         else:             return redirect(url_for("fail"))     return render_template("file_name.html") @app.route("/uploads") def successful():     """     设置返回路径的视图函数     :return:     """     url = url_for("file_name")     return '访问文件的路径：http://127.0.0.1:5000{}'.format(url) @app.route("/fail") def fail():     """     文件类型不符合的视图函数     :return:     """     return "文件不符合规则" if __name__ == '__main__':     app.run(debug=True)