如何使用此 javascript 函数将变量发送到表单？

How can I send a variable to a form using this javascript function?

提问by NCoder

I've got this onclick call:

我有这个 onclick 电话：

onClick="mySubmit();

which calls this function:

它调用这个函数：

function mySubmit(){
    document.getElementById("myForm").submit();
}

which then submits this form:

然后提交此表单：

<form id="myForm" action="action.php" method="post">

My question is:how do I send a variable to the form from the onClick to get something like <form id="myForm" action="action.php?id=**(the variable sent from the onclick goes here)**" method="post">

我的问题是：如何从 onClick 向表单发送变量以获取类似<form id="myForm" action="action.php?id=**(the variable sent from the onclick goes here)**" method="post">

Thanks!

谢谢！

回答by Juan Mendes

Easiest way: append a hidden field to the form.

最简单的方法：在表单中附加一个隐藏字段。

<form id="myForm" action="action.php" method="post">
  <input type='hidden' id= 'hiddenField' name='id' value='' />

<script> 
  function mySubmit() {
     document.getElementById('hiddenField').value = "Whatever I want here";
     document.getElementById("myForm").submit();
   }
</script>

Or use a function like

或者使用像这样的函数

function addHiddenField(form, props) {
  Object.keys(props).forEach(fieldName => {
    var field = form[fieldName];
    if (!field) {
      field = document.createElement('input');
      field.type = 'hidden';
      field.name = fieldName;
      form.appendChild(field);
    }
    field.value = props[fieldName];
  });
}

document.querySelector('form').addEventListener('submit', () => {
  addHiddenField(this, {
    someQueryName: 'someQueryValue',
    otherQueryName: 'otherVal'
  });
});

<form>
  Name
  <input name=name />
  <input type=submit />
</form>

Note that you can use DevTools to modify the iframe's sandbox to allow it to submit forms and you can verify the posted URL. sandbox="... allow-forms"

请注意，您可以使用 DevTools 修改 iframe 的沙箱以允许它提交表单，并且您可以验证发布的 URL。 sandbox="... allow-forms"

回答by Waqas Raja

place a input type hidden inside the form then submit the form

将输入类型隐藏在表单中，然后提交表单

<input id="id" name="id" type="hidden" />

set the value of the hidden field in your javascript submit()

在 javascript submit() 中设置隐藏字段的值

document.getElementById('id').value = **;

but by setting form method="post" the id will not be the part of query string, i.e. the url will remain action.php instead if you really want the id in query string i.e. url action.php?id=** then you need to change the form method="get", by this the hidden field id will automatically be the part of the url i.e action.php?id=**

但是通过设置 form method="post" id 将不是查询字符串的一部分，即 url 将保留 action.php 而不是如果你真的想要查询字符串中的 id ie url action.php?id=** 那么你需要更改表单method="get"，这样隐藏字段id将自动成为url的一部分，即action.php?id=**

read about difference between get and post

阅读get 和 post 之间的区别

here is how you access posted value on next pageif you really need to use method="post" action="action.php"

如果您确实需要使用 method="post" action="action.php"，这是访问下一页上发布的值的方法

回答by Waqas Raja

Your HTML :

你的 HTML ：

<form id="myForm" action="#" method="post">
            <input type='hidden' id="id" name='id' value='123' />
            <input type='submit' name='submit' value='Click me !' onclick='addParam()' />
        </form>

Your Script :

你的脚本：

function addParam() {

                var url = "action.php?id=" + document.getElementById('id').value;
                document.getElementById("myForm").setAttribute('action', url);

            }

Thank You.

谢谢你。