使用Fetch API

function submitForm(e, form){
    e.preventDefault();
    
    fetch('file.php', {
      method: 'post',
      body: JSON.stringify({name: form.formName.value, email: form.formEmail.value})
    }).then(function(response) {
      return response.json();
    }).then(function(data) {
      //Success code goes here
      alert('form submited')
    }).catch(function(err) {
      //Failure
      alert('Error')
    });
}

<form action="file.php" method="post" onsubmit="submitForm(event, this)">
    <input name="formName" type="text" />
    <input name="formEmail" type="email" />
    <input name="formSubmit" type="submit" value="Submit Me!" />
</form>

我建议使用FormData，它使用的格式与表单在编码类型设置为“multipart/form-data”时使用的格式相同。

const submitForm = () => {
        const formEl = document.getElementById('formId');
        const payload = new FormData(formEl);

        fetch('file.php', {
            method: 'POST',
            body: payload,
        })
        .then(Result => Result.json())
        .then(data => {
            console.log(data);
            // your code comes here
        })
        .catch(errorMsg => {
            console.log(errorMsg);
        });

    };