Question

我希望在编辑表单时将表单中的数据预先填充

views.py

def edit_task(request, post_id):
    post = Post.objects.get(id=post_id)
    form = TaskForm(request.POST, instance=post)
    if request.method == 'POST':
        print(request.POST)
        form = TaskForm(request.POST, instance=post)
        if form.is_valid():
            form.save()
            return redirect('task')
    context = {'form': form}
    return render(request, 'List/add_task.html', context)

add_task.html

{% extends "List/Home.html" %}
{% block content %}

<form action="" method="post">
    {% csrf_token %}
    {{ form.as_p }}
    <input type="submit">
    
</form>

{% endblock content %}

Answer 1

您可以使用数据填充此表单，并提供return "${df.format(length / 1024.f)} KB";

initial

Answer 2

请仔细考虑如何实例化表单。目前，您正在对GET和POST请求使用相同的代码TaskForm(request.POST, instance=post)：

def edit_task(request, post_id):
    post = Post.objects.get(id=post_id)
    form = TaskForm(request.POST, instance=post)
    if request.method == 'POST':
        print(request.POST)
        form = TaskForm(request.POST, instance=post)
        ...

但是request.POST对于GET请求为空，因此，当使用GET请求加载表单时，您会得到一个带有错误的空表单。

您可以通过删除GET请求的request.POST来解决此问题

def edit_task(request, post_id):
    post = Post.objects.get(id=post_id)
    # Instantiate form without any data
    form = TaskForm(instance=post)
    if request.method == 'POST':
        print(request.POST)
        # replace the form for POST requests
        form = TaskForm(request.POST, instance=post)
        ...

使用if...else而不是替换表单可能更清楚：

def edit_task(request, post_id):
    post = Post.objects.get(id=post_id)
    if request.method == 'POST':
        print(request.POST)
        # instantiate form for POST requests
        form = TaskForm(request.POST, instance=post)
        ...
    else:
        # instantiate the form for GET requests
        form = TaskForm(instance=post)
    context = {'form': form}
    return render(request, 'List/add_task.html', context)

我如何预先填充此更新表格

2 个答案: