Question

在我正在研究的Flask函数的GET部分中，我有一些用Python 3编写的非常简单的代码。我试图传入的数据永远不会显示在我的HTML渲染上。

@app.route("/sellselected", methods=["GET", "POST"])
@login_required
def sellselected(order_num):
    if request.method == "POST":
        #not done, just have a redirect to index
    else:
        stock_to_sell = db.execute("SELECT * FROM purchases WHERE order_num = :order_num", order_num=order_num)
        #stock_to_sell = ['fish']

    return render_template("sellselected.html", stock_to_sell=stock_to_sell, order_num=order_num)

SQL语句似乎没有任何传递，它在HTML渲染上只是空白。但作为测试，我也使用'鱼'，它也是无/空。

Jinja看起来像：

{% block main %}
<list>
    <ul>{{ stock_to_sell }}</ul>
    <ul>{{ order_num }}</ul>
</list>
{% endblock %}

因此页面正文中包含订单号，但stock_to_sell始终为空。

Answer 1

你的问题不再与jinja有关。您的路线错误，应该是：@app.route("/sellselected/<order_num>", methods=["GET", "POST"])。

因为你将order_num传递给sellselected函数所以你需要在路由上声明它。

Answer 2

你说你想把param order_num传递给GET吗？因为代码说POST被重定向到索引。

所以，你将param作为GET传递。你需要先得到它

current_order = request.args.get（＆＃39; order_num＆＃39;）

您的代码应为：

@app.route("/sellselected", methods=["GET", "POST"])
@login_required
def sellselected(order_num):
    if request.method == "POST":
        # not done, just have a redirect to index
    else:
        order_num = request.args.get('order_num')
        stock_to_sell = db.execute("SELECT * FROM purchases WHERE order_num = :order_num", order_num=order_num)

return render_template("sellselected.html", stock_to_sell=stock_to_sell, order_num=order_num)

Answer 3

请注意，如果您遍历一个对象，那么它的内容将返回为空。这是因为结果是一个生成器，它的值只能被访问一次。

无法工作，因为 gcp_certs 已被迭代：

  gcp_certs = connection.execute(query)
  for cert in gcp_certs:
     print(cert.name)
    
  return render_template('certifications.html',
                           gcpcerts=gcp_certs,
                           now=datetime.utcnow(),
                           cookie=token)

作品：

  gcp_certs = connection.execute(query)
  return render_template('certifications.html',
                           gcpcerts=gcp_certs,
                           now=datetime.utcnow(),
                           cookie=token)

一种解决方案：

imports copy

gcp_certs = list(connection.execute(query))
sql_select = ''
for cert in copy.copy(gcp_certs):
     print(cert.name)

return render_template('certifications.html',
                           gcpcerts=gcp_certs,
                           now=datetime.utcnow(),
                           cookie=token)

Python Flask Jinja SQL：没有值传递给模板

3 个答案: