如何检查所有四个多重选择是否都选择了某个值? [英] How to check if all the four multiselect has some value selected?

问题描述

我有4种multiselect，都是通过这种方式动态创建的

I have 4 multiselect which are created dynamically by this fashion

var drp_nt = $('<select />', {
                              'id'     : 'drp_' + nt,
                              'name'   : 'drp_' + nt+'[]',
                              'multiple': true});

var drp_cnt = $('<select />', {
                              'id'     : 'drp_' + cnt,
                              'name'   : 'drp_' + cnt+'[]',
                              'multiple': true});

var drp_ctg = $('<select />', {
                              'id'     : 'drp_' + ctg,
                              'name'   : 'drp_' + ctg+'[]',
                              'multiple': true});

var drp_api = $('<select />', {
                              'id'     : 'drp_' + api,
                              'name'   : 'drp_' + api+'[]',
                              'multiple': true});

现在我要创建一个名为

function check_selection()
{
-----------------
-----------------
}

其中将包含用于检查所有multiselect是否选择了任何数据的代码.

which will contain the code to check whether all of the multiselect has any of the data selected.

我又如何从所有4个multiselect下拉菜单中使用and事件调用此函数(因为只要从任何multiselect中选择了任何选项，此函数都会被触发)

Also how can I call this function by using and event from all the 4 multiselect dropdowns(since this function will be triggered whenever any option is selected from any of the multiselect)

我尝试了多次选择的onchange事件，但没有调用该函数.

I tried the onchange event for multiselect, but it didn't call the function.

推荐答案

使用change event选中所有选择框，或者不使用 filter()

use change event to check all select box is selected or not using filter()

$("select").change(function () {

    var selectedBox = $("select").filter(function () {
        return this.value != "";
    });
    if (selectedBox.length == 4) {
        alert("4 ckecked")
    }

});

对于动态元素

$(document).on("change", "select[id^=drp_]", function(){
       var selectedBox = $("select").filter(function () {
            return this.value != "";
        });
        if (selectedBox.length == 4) {
            alert("4 ckecked")
        }

    });

DEMO

DEMO

这篇关于如何检查所有四个多重选择是否都选择了某个值?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！