烧瓶将变量从一个函数传递到另一个函数

Question

As you can see the code. I want to pass variable q from function home() into function search() .

@app.route("/",methods=['GET','POST'])
def home():
    result = Mylist.query.all()
    return render_template('index.html',result=result)
    q = request.form.get("q")

@app.route("/search.html")
def search():
        d = q
        var='%'+d+'%'
        result = Mylist.query.filter(Mylist.type.like(var)
        return render_template('search.html',result=result)

Answer 1

Where an index.html will contain:

<form action="/search.html" method="get" autocomplete="off" class="subscribe-form">
     <div class="form-group d-flex">
         <input type="text" class="form-control" placeholder="Enter your search" name="q" id="q" value="{{q}}">
         <input type="submit" value="Search" class="submit px-3">
     </div>
 </form>

Now you will see /search.html?q=top in url now you can easily pass this q=top by using q=request.args.get("q") ...

@app.route("/search.html",methods=['GET'])
def search():
        q =request.args.get("q")
        d=str(q)
        var='%'+d+'%'
        myresult = Mylist.query.filter(Mylist.type.like(var)| Mylist.title.like(var)).all()

Answer 2

Option 1:

A variable created and updated inside a function exists only for that function.

From the Python documentation ...

"If a variable is assigned a value anywhere within the function's body, it's assumed to be a local unless explicitly declared as global."

Solution:
Create q as a variable outside of functions , this way it's not just trapped inside function home but instead is now universally available to any and all functions. Any function can use or update such a variable.

Option 2:

Alternatively, you could just try passing q as a function parameter .

In example below, you will call function search but with parameter q added. The search function itself will reference that same q as a thing called input (or choose your own name/word).

@app.route("/",methods=['GET','POST'])
def home():
    result = Mylist.query.all()
    q = request.form.get("q")
    search( q )
    return render_template('index.html',result=result)


@app.route("/search.html")
def search( input ):
    d = input
    var='%'+d+'%'
    result = Mylist.query.filter(Mylist.type.like(var)
    return render_template('search.html',result=result)

Answer 3

Define a global list append the variable from first view function to the list and access the last index value in the second view function.

var_list = []
@app.route("/",methods=['GET','POST'])
def home():
    result = Mylist.query.all()
    return render_template('index.html',result=result)
    q = request.form.get("q")
    var_list.append(q)

@app.route("/search.html")
def search():
        d = var_list.pop()
        var='%'+d+'%'
        result = Mylist.query.filter(Mylist.type.like(var)
        return render_template('search.html',result=result)

Answer 4

your index.html will contain

<form action="/search.html" method="get" autocomplete="off" class="subscribe-form">
     <div class="form-group d-flex">
         <input type="text" class="form-control" placeholder="Enter your search" name="q" id="q" value="{{q}}">
         <input type="submit" value="Search" class="submit px-3">
     </div>
 </form>

==================================================================================

Now you will see /search.html?q=top in url now you can easily pass this q=top by using

q=request.args.get("q")