flask 基础5

from flask import Flask, render_template, send_file

app = Flask(__name__)


@app.before_request
def be1():
    print(‘be1‘)
    return None


@app.before_request
def be2():
    print(‘be2‘)
    return None
    # return "error"


@app.before_request
def be3():
    print(‘be3‘)
    return None
    # return "error"


@app.after_request
def af1(res):
    print(‘af1‘)
    return res


@app.after_request
def af2(res):
    print(‘af2‘)
    return res


@app.after_request
def af3(res):
    print(‘af3‘)
    return res


@app.route("/info", methods=["GET", "POST"])
def info():
    return render_template("info.html")


@app.errorhandler(404)
def error404(error_message):
    print(error_message)
    return send_file(‘1.png‘) #404可以不单单返回信息  可以返回图片  音乐等等

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