提交后如何仅清除表单中的特定字段？答案

【问题标题】：How to clear only a specific field from a form after submission?提交后如何仅清除表单中的特定字段？
【发布时间】：2020-03-29 10:45:26
【问题描述】：

我有一个包含几个字段的表单。大多数情况下，人们每次提交时只需要更改一个字段，而不是全部，所以我想将其更改为提交时只清除员工字段，但工作区选择和站（如果有任何可用）保持选中状态。

如何更改表单的处理方式，使其在提交时不会完全清除？我知道 form = WarehouseForm() 是清除它的原因，但我不确定如何指定我只想清除 employee_number 字段。

views.py

def enter_exit_area(request):
    enter_without_exit = None
    exit_without_enter = None

    if request.method == 'POST':
        form = WarehouseForm(request.POST)

        if form.is_valid():
            emp_num = form.cleaned_data['employee_number']
            area = form.cleaned_data['work_area']
            station = form.cleaned_data['station_number']

            if 'enter_area' in request.POST:
                # Submission logic
                form = WarehouseForm()

            elif 'leave_area' in request.POST:
                # Submission logic ..

                form = WarehouseForm()
    else:
        form = WarehouseForm()
    return render(request, "operations/enter_exit_area.html", {
        'form': form,
        'enter_without_exit': enter_without_exit,
        'exit_without_enter': exit_without_enter,
    })

【问题讨论】：

查看这个帖子：stackoverflow.com/questions/813418/…

标签： python django

【解决方案1】：

如果它是输入类型的文本框，那么您也可以在 javascript 中执行如下操作：例如：document.getElementById("formFieldId").value = '';

【讨论】：

【解决方案2】：

您可以使用initial 参数：

if 'enter_area' in request.POST:
    # Submission logic
    form = WarehouseForm(initial={'employee_number': '', 'work_area': area, 'station_number': station})

请注意，employee_number 字段为空白。

您尚未包含提交逻辑，因此您的实现可能会略有不同。但原理是一样的。

【讨论】：

【解决方案3】：

form_obj = form.save(commit=False)
form_obj.employee_number = '' # if you want to clear employee_number field
form_obj.save()


Note:- 'employee_number' field should be null=True in models.py, so that you can clear the field

For Example:- 

def enter_exit_area(request):
    enter_without_exit = None
    exit_without_enter = None

    if request.method == 'POST':
        form = WarehouseForm(request.POST)

        if form.is_valid():
            emp_num = form.cleaned_data['employee_number']
            area = form.cleaned_data['work_area']
            station = form.cleaned_data['station_number']

            if 'enter_area' in request.POST:
                # Submission logic
                form_obj = form.save(commit=False)
        form_obj.employee_number = '' # if you want to clear employee_number field

            elif 'leave_area' in request.POST:
                # Submission logic ..
        form_obj = form.save(commit=False)
        form_obj.employee_number = '' # if you want to clear employee_number field

    form_obj.save()
    else:
        form = WarehouseForm()

    return render(request, "operations/enter_exit_area.html", {
        'form': form,
        'enter_without_exit': enter_without_exit,
        'exit_without_enter': exit_without_enter,
    })

【讨论】：