我使用这个jQuery块，它将在提交时为每个未选中的复选框添加一个隐藏输入。它将保证您每次都为每个复选框提交一个值，而不会弄乱您的标记，并冒着忘记在稍后添加的复选框上执行此操作的风险。它也与您正在使用的任何后端堆栈(PHP、Ruby等)无关。

// Add an event listener on #form's submit action...
$("#form").submit(
    function() {

        // For each unchecked checkbox on the form...
        $(this).find($("input:checkbox:not(:checked)")).each(

            // Create a hidden field with the same name as the checkbox and a value of 0
            // You could just as easily use "off", "false", or whatever you want to get
            // when the checkbox is empty.
            function(index) {
                var input = $('<input />');
                input.attr('type', 'hidden');
                input.attr('name', $(this).attr("name")); // Same name as the checkbox
                input.attr('value', "0"); // or 'off', 'false', 'no', whatever

                // append it to the form the checkbox is in just as it's being submitted
                var form = $(this)[0].form;
                $(form).append(input);

            }   // end function inside each()
        );      // end each() argument list

        return true;    // Don't abort the form submit

    }   // end function inside submit()
);      // end submit() argument list

“我有一大堆默认选中的复选框”——这就是我解决问题的方法:

if(($C1)OR($C2)OR... ($C18)){echo "some are checked!";} else{$C1='set';$C2='set';$C3='set';$C4='set';$C5='set';$C6='set';$C7='set';$C8='set';$C9='set';$C10='set';$C11='set';$C12='set';$C13='set';$C14='set';$C15='set';$C16='set';$C17='set';$C18='set';} //(if all are unchecked - set them to 'check' since its your default) the above line will execute the echo if some are unchecked but the checked ones will still have the value parameter set therefore, to keep them set, when writing them in the form, use if($C1){echo "checked";} use the values in the further logic...

! !这种方法的局限性:你不能取消选中所有的东西——它们都会被重新选中

您不需要为所有复选框创建一个隐藏字段，只需复制我的代码。 它会改变复选框的值，如果不选中，值将赋值为0，如果选中复选框，则将值赋值为1

$("form").submit(function () {

    var this_master = $(this);

    this_master.find('input[type="checkbox"]').each( function () {
        var checkbox_this = $(this);


        if( checkbox_this.is(":checked") == true ) {
            checkbox_this.attr('value','1');
        } else {
            checkbox_this.prop('checked',true);
            //DONT' ITS JUST CHECK THE CHECKBOX TO SUBMIT FORM DATA    
            checkbox_this.attr('value','0');
        }
    })
})

这是对之前答案的一种尝试，以自动保留具有特定值(在本例中为0)的未选中复选框，而不会在提交时选中所有复选框。

$("form").submit(function () {
    let this_master = $(this);

    // Remove any of the hidden values that may already be there (if the user previously canceled the submit)
    this_master.find("*[id^='hiddenchkinput_']").remove();

    // Get all unchecked checkboxes
    this_master.find('input:checkbox:not(:checked)').each(function () {
      let thisChk = $(this);

      // Create a hidden input with the same name as the checkbox
      let newInput = document.createElement('input');
      $(newInput).attr('name', thisChk.attr('id'))
        .attr('id', 'hiddenchkinput_' + thisChk.attr('id'))
        .attr('type', 'hidden')
        .val('0');
      // Append the new input to the end of the form
      this_master.append(newInput);
    });
})

我先试了山姆的版本。 好主意，但它会导致表单中有多个具有相同名称的元素。如果您使用任何基于名称查找元素的javascript，它现在将返回一个元素数组。

我已经在PHP中解决了Shailesh的想法，它为我工作。 这是我的代码:

/* Delete '.hidden' fields if the original is present, use '.hidden' value if not. */
foreach ($_POST['frmmain'] as $field_name => $value)
{
    // Only look at elements ending with '.hidden'
    if ( !substr($field_name, -strlen('.hidden')) ) {
        break;
    }

    // get the name without '.hidden'
    $real_name = substr($key, strlen($field_name) - strlen('.hidden'));

    // Create a 'fake' original field with the value in '.hidden' if an original does not exist
    if ( !array_key_exists( $real_name, $POST_copy ) ) {
        $_POST[$real_name] = $value;
    }

    // Delete the '.hidden' element
    unset($_POST[$field_name]);
}

对于复选框，一个不使用隐藏类型值的简单方法是:

< >形式 <input type='checkbox' name='self - destruct' value='1'> > < /形式

在PHP中，对于表单数据的发布:

// Sanitize form POST data
$post = filter_var_array($_POST, FILTER_SANITIZE_STRING);

// set the default checkbox value
$selfDestruct = '0';
if(isset($post["selfdestruct"]))
    $selfDestruct = $post["selfdestruct"];