限制复选框最多选择几项

JS

window.onload = function(){
	var _forbidcheckSelects = document.getElementsByName("forbidcheckSelects"),
	//限制复选框最多选择3项
			banNums = 3;
	for(var i in _forbidcheckSelects){
		_forbidcheckSelects[i].onclick = function(){
			var __forbidcheckSelects = document.getElementsByName("forbidcheckSelects"),
					selectNum = 0;
			for(var i in __forbidcheckSelects){
				if(i == "length") break;
				if(__forbidcheckSelects[i].checked){
					selectNum++;
				}
			}
			//如果选中的复选项，超过限制最大数，将当前的选中选项设置为没选中false
			if(selectNum > banNums) {
				this.checked = false;
			}

		}
	}
};