Flask 内部服务器错误但没有错误日志

问题描述

我是 Flask 的新手，并尝试从 GeeksForGeeks 运行这个简单的代码

form.html

<form action="{{ url_for("gfg")}}" method="post">
<label for="firstname">First Name:</label>
<input type="text" id="firstname" name="fname" placeholder="firstname">
<label for="lastname">Last Name:</label>
<input type="text" id="lastname" name="lname" placeholder="lastname">
<button type="submit">Login</button>

flask_text.py

# importing Flask and other modules
from flask import Flask,request,render_template

# Flask constructor
app = Flask(__name__)

# A decorator used to tell the application
# which URL is associated function
@app.route('/',methods =["GET","POST"])
def gfg():
    if request.method == "POST":
    # getting input with name = fname in HTML form
    first_name = request.form.get("fname")
    # getting input with name = lname in HTML form
    last_name = request.form.get("lname")
    return "Your name is "+first_name + last_name
    return render_template("form.html")

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

https://www.geeksforgeeks.org/retrieving-html-from-data-using-flask/

您可以在上面的链接中找到代码 我添加了 app.debug = True 但没有错误日志

我的 html 文件在 /templates 文件夹中

解决方法

首先，你的代码缩进是错误的。试试这个：

# importing Flask and other modules
from flask import Flask,request,render_template 
  
# Flask constructor
app = Flask(__name__)   
  
# A decorator used to tell the application
# which URL is associated function
@app.route('/',methods =["GET","POST"])
def gfg():
    if request.method == "POST":
       # getting input with name = fname in HTML form
       first_name = request.form.get("fname")
       # getting input with name = lname in HTML form 
       last_name = request.form.get("lname") 
       return "Your name is "+first_name + last_name
    return render_template("form.html")
  
if __name__=='__main__':
   app.run()

其次，您的虚拟环境是否正在运行？ （你能在命令行的开头看到 '(env)' 吗？） 如果没有，则需要先执行：

source env/bin/activate

然后pip3安装烧瓶

如果它仍然不起作用，请给我更多的上下文。