输入类型复选框值

Question

我在看this w3schools checkbox demo

我注意到检查时输入没有得到检查值。这是有效的HTML吗？

我尝试在php表单中使用它，如果选中“on”则使用值。

.container {
  display: block;
  position: relative;
  padding-left: 35px;
  margin-bottom: 12px;
  cursor: pointer;
  font-size: 22px;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}


/* Hide the browser's default checkbox */

.container input {
  position: absolute;
  opacity: 0;
  cursor: pointer;
}


/* Create a custom checkbox */

.checkmark {
  position: absolute;
  top: 0;
  left: 0;
  height: 25px;
  width: 25px;
  background-color: #eee;
}


/* On mouse-over, add a grey background color */

.container:hover input~.checkmark {
  background-color: #ccc;
}


/* When the checkbox is checked, add a blue background */

.container input:checked~.checkmark {
  background-color: #2196F3;
}


/* Create the checkmark/indicator (hidden when not checked) */

.checkmark:after {
  content: "";
  position: absolute;
  display: none;
}


/* Show the checkmark when checked */

.container input:checked~.checkmark:after {
  display: block;
}


/* Style the checkmark/indicator */

.container .checkmark:after {
  left: 9px;
  top: 5px;
  width: 5px;
  height: 10px;
  border: solid white;
  border-width: 0 3px 3px 0;
  -webkit-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  transform: rotate(45deg);
}

<h1>Custom Checkboxes</h1>
<label class="container">One
  <input type="checkbox" checked="checked">
  <span class="checkmark"></span>
</label>
<label class="container">Two
  <input type="checkbox">
  <span class="checkmark"></span>
</label>
<label class="container">Three
  <input type="checkbox">
  <span class="checkmark"></span>
</label>
<label class="container">Four
  <input type="checkbox">
  <span class="checkmark"></span>
</label>

Answer 1

复选框的值是value属性所说的（在复选框的情况下）on作为默认值。

其检查状态（可通过JS中的checked属性获得）确定它是否是一个成功的控件（即完全出现在提交的表单数据中）。

Answer 2

只需删除checked="checked"，以便不检查该初始值

＆＃13;

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/* When the checkbox is checked, add a blue background */

.container input:checked~.checkmark {
  background-color: #2196F3;
}


/* Create the checkmark/indicator (hidden when not checked) */

.checkmark:after {
  content: "";
  position: absolute;
  display: none;
}


/* Show the checkmark when checked */

.container input:checked~.checkmark:after {
  display: block;
}


/* Style the checkmark/indicator */

.container .checkmark:after {
  left: 9px;
  top: 5px;
  width: 5px;
  height: 10px;
  border: solid white;
  border-width: 0 3px 3px 0;
  -webkit-transform: rotate(45deg);
  -ms-transform: rotate(45deg);
  transform: rotate(45deg);
}

＆＃13;

<h1>Custom Checkboxes</h1>
<label class="container">One
  <input type="checkbox">
  <span class="checkmark"></span>
</label>
<label class="container">Two
  <input type="checkbox">
  <span class="checkmark"></span>
</label>
<label class="container">Three
  <input type="checkbox">
  <span class="checkmark"></span>
</label>
<label class="container">Four
  <input type="checkbox">
  <span class="checkmark"></span>
</label>

＆＃13;

＆＃13;

＆＃13;