简而言之:使用change
事件.这里有几个实际的例子.由于我误解了问题,我将包括jQuery示例和普通JavaScript.不过,使用jQuery不会获得太多好处.
var checkbox = document.querySelector("input[name=checkbox]");
checkbox.addEventListener('change', function() {
if (this.checked) {
console.log("Checkbox is checked..");
} else {
console.log("Checkbox is not checked..");
}
});
<input type="checkbox" name="checkbox" />
$('input[name=checkbox]').change(function() {
if ($(this).is(':checked')) {
console.log("Checkbox is checked..")
} else {
console.log("Checkbox is not checked..")
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="checkbox" name="checkbox" />
以下是复选框列表的示例.要 Select 多个元素,我们使用querySelectorAll
而不是querySelector
.然后使用Array.filter
和Array.map
提取校验值.
// Select all checkboxes with the name 'settings' using querySelectorAll.
var checkboxes = document.querySelectorAll("input[type=checkbox][name=settings]");
let enabledSettings = []
/*
For IE11 support, replace arrow functions with normal functions and
use a polyfill for Array.forEach:
https://vanillajstoolkit.com/polyfills/arrayforeach/
*/
// Use Array.forEach to add an event listener to each checkbox.
checkboxes.forEach(function(checkbox) {
checkbox.addEventListener('change', function() {
enabledSettings =
Array.from(checkboxes) // Convert checkboxes to an array to use filter and map.
.filter(i => i.checked) // Use Array.filter to remove unchecked checkboxes.
.map(i => i.value) // Use Array.map to extract only the checkbox values from the array of objects.
console.log(enabledSettings)
})
});
<label>
<input type="checkbox" name="settings" value="forcefield">
Enable forcefield
</label>
<label>
<input type="checkbox" name="settings" value="invisibilitycloak">
Enable invisibility cloak
</label>
<label>
<input type="checkbox" name="settings" value="warpspeed">
Enable warp speed
</label>
let checkboxes = $("input[type=checkbox][name=settings]")
let enabledSettings = [];
// Attach a change event handler to the checkboxes.
checkboxes.change(function() {
enabledSettings = checkboxes
.filter(":checked") // Filter out unchecked boxes.
.map(function() { // Extract values using jQuery map.
return this.value;
})
.get() // Get array.
console.log(enabledSettings);
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<label>
<input type="checkbox" name="settings" value="forcefield">
Enable forcefield
</label>
<label>
<input type="checkbox" name="settings" value="invisibilitycloak">
Enable invisibility cloak
</label>
<label>
<input type="checkbox" name="settings" value="warpspeed">
Enable warp speed
</label>