404未找到“未找到请求的URL”

Question

I'm trying to make a button in sida2 take me to resultat and post the information named MJ from the input form but I get an error 404 The requested URL was not found on the server and I don't understand why. This is the html part:

<form action="/sida2/resultat.html" method="POST">
<input title="" placeholder="MJ/kq foder" type="text" name="MJ" required>
<br>
<button type="submit">Submit</button>
</form>

And this is the python part:

from flask import Flask, render_template, request

app=Flask(__name__)

@app.route('/')
def home():
    return(render_template("hemsida.html")) 


@app.route('/sida2/', methods=['POST', 'GET'])
def sida2():
    return(render_template("andrasidan.html"))


@app.route('/sida2/resultat', methods=['POST'])
def resultat():    
    if request.method=='POST':       
        mj= request.form["MJ"]



    return(render_template("resultat.html"))

if __name__ =="__main__":
    app.run(debug=True)

I assume it's something obvious I'm missing but I just can't seem to find it.

Answer 1

Use url_for to generate URLs to Flask views. The view you want is resultat .

<form action="{{ url_for('resultat') }}" method="POST">

This will generate the appropriate URL for your resultat() function:

@app.route('/sida2/resultat', methods=['POST'])
def resultat():

The URL you currently have in your form action ( /sida2/resultat.html ) will not work as your code binds to the URL /sida2/resultat instead.

For a quick overview of the benefits of why you should use url_for over hardcoding your URLs, check out the Flask quickstart section on the topic .