如何获取页面上所有选中复选框的计数

使用 size() 方法或 length 财产。长度属性是首选的,因为它更快。

例子:

var count = $("[type='checkbox']:checked").length;

使用jQuery:

var cbs = $("input:checkbox"); //find all checkboxes
var nbCbs = cbs.length; //the number of checkboxes

var checked = $("input[@type=checkbox]:checked"); //find all checked checkboxes + radio buttons
var nbChecked = checked.length;

使用javascript:

var inputs = document.getElementsByTagName("input"); //or document.forms[0].elements;
var cbs = []; //will contain all checkboxes
var checked = []; //will contain all checked checkboxes
for (var i = 0; i < inputs.length; i++) {
  if (inputs[i].type == "checkbox") {
    cbs.push(inputs[i]);
    if (inputs[i].checked) {
      checked.push(inputs[i]);
    }
  }
}
var nbCbs = cbs.length; //number of checkboxes
var nbChecked = checked.length; //number of checked checkboxes

来源: How to find Checkboxes? at coderanch