适用于开启/关闭多种模式

jQuery(function()
{
    jQuery(document).on('show.bs.modal', '.modal', function()
    {
        var maxZ = parseInt(jQuery('.modal-backdrop').css('z-index')) || 1040;

        jQuery('.modal:visible').each(function()
        {
            maxZ = Math.max(parseInt(jQuery(this).css('z-index')), maxZ);
        });

        jQuery('.modal-backdrop').css('z-index', maxZ);
        jQuery(this).css("z-index", maxZ + 1);
        jQuery('.modal-dialog', this).css("z-index", maxZ + 2);
    });

    jQuery(document).on('hidden.bs.modal', '.modal', function () 
    {
        if (jQuery('.modal:visible').length)
        {
            jQuery(document.body).addClass('modal-open');

           var maxZ = 1040;

           jQuery('.modal:visible').each(function()
           {
               maxZ = Math.max(parseInt(jQuery(this).css('z-index')), maxZ);
           });

           jQuery('.modal-backdrop').css('z-index', maxZ-1);
       }
    });
});

演示

https://www.bootply.com/cObcYInvpq#

每次你运行sys。showModal函数增加z-index并将其设置为新的模态。

function system() {

    this.modalIndex = 2000;

    this.showModal = function (selector) {
        this.modalIndex++;

        $(selector).modal({
            backdrop: 'static',
            keyboard: true
        });
        $(selector).modal('show');
        $(selector).css('z-index', this.modalIndex );       
    }

}

var sys = new system();

sys.showModal('#myModal1');
sys.showModal('#myModal2');

Bootstrap 4.5的简单解决方案

.modal.fade {
  background: rgba(0, 0, 0, 0.5);
}

.modal-backdrop.fade {
  opacity: 0;
}

更新日期:2019年1月22日，13.41 我通过jhay优化了解决方案，它还支持关闭和打开相同或不同的对话框，例如，从一个细节数据向前或向后跨步到另一个细节数据。

(function ($, window) {
'use strict';

var MultiModal = function (element) {
    this.$element = $(element);
    this.modalIndex = 0;
};

MultiModal.BASE_ZINDEX = 1040;

/* Max index number. When reached just collate the zIndexes */
MultiModal.MAX_INDEX = 5;

MultiModal.prototype.show = function (target) {
    var that = this;
    var $target = $(target);

    // Bootstrap triggers the show event at the beginning of the show function and before
    // the modal backdrop element has been created. The timeout here allows the modal
    // show function to complete, after which the modal backdrop will have been created
    // and appended to the DOM.

    // we only want one backdrop; hide any extras
    setTimeout(function () {
        /* Count the number of triggered modal dialogs */
        that.modalIndex++;

        if (that.modalIndex >= MultiModal.MAX_INDEX) {
            /* Collate the zIndexes of every open modal dialog according to its order */
            that.collateZIndex();
        }

        /* Modify the zIndex */
        $target.css('z-index', MultiModal.BASE_ZINDEX + (that.modalIndex * 20) + 10);

        /* we only want one backdrop; hide any extras */
        if (that.modalIndex > 1) 
            $('.modal-backdrop').not(':first').addClass('hidden');

        that.adjustBackdrop();
    });

};

MultiModal.prototype.hidden = function (target) {
    this.modalIndex--;
    this.adjustBackdrop();

    if ($('.modal.in').length === 1) {

        /* Reset the index to 1 when only one modal dialog is open */
        this.modalIndex = 1;
        $('.modal.in').css('z-index', MultiModal.BASE_ZINDEX + 10);
        var $modalBackdrop = $('.modal-backdrop:first');
        $modalBackdrop.removeClass('hidden');
        $modalBackdrop.css('z-index', MultiModal.BASE_ZINDEX);

    }
};

MultiModal.prototype.adjustBackdrop = function () {        
    $('.modal-backdrop:first').css('z-index', MultiModal.BASE_ZINDEX + (this.modalIndex * 20));
};

MultiModal.prototype.collateZIndex = function () {

    var index = 1;
    var $modals = $('.modal.in').toArray();


    $modals.sort(function(x, y) 
    {
        return (Number(x.style.zIndex) - Number(y.style.zIndex));
    });     

    for (i = 0; i < $modals.length; i++)
    {
        $($modals[i]).css('z-index', MultiModal.BASE_ZINDEX + (index * 20) + 10);
        index++;
    };

    this.modalIndex = index;
    this.adjustBackdrop();

};

function Plugin(method, target) {
    return this.each(function () {
        var $this = $(this);
        var data = $this.data('multi-modal-plugin');

        if (!data)
            $this.data('multi-modal-plugin', (data = new MultiModal(this)));

        if (method)
            data[method](target);
    });
}

$.fn.multiModal = Plugin;
$.fn.multiModal.Constructor = MultiModal;

$(document).on('show.bs.modal', function (e) {
    $(document).multiModal('show', e.target);
});

$(document).on('hidden.bs.modal', function (e) {
    $(document).multiModal('hidden', e.target);
});}(jQuery, window));

在modal.js中添加全局变量

var modalBGIndex = 1040; // modal backdrop background
var modalConIndex = 1042; // modal container data 

//添加变量modal .prototype. background

var e    = $.Event('show.bs.modal', { relatedTarget: _relatedTarget })

modalConIndex = modalConIndex + 2; // add this line inside "Modal.prototype.show"

that.$element
    .show()
    .scrollTop(0)
that.$element.css('z-index',modalConIndex) // add this line after show modal 

if (this.isShown && this.options.backdrop) {
      var doAnimate = $.support.transition && animate

      modalBGIndex = modalBGIndex + 2; // add this line increase modal background index 2+

this.$backdrop.addClass('in')
this.$backdrop.css('z-index',modalBGIndex) // add this line after backdrop addclass

我意识到一个答案已经被接受，但我强烈建议不要破解bootstrap来解决这个问题。

通过连接show .bs.modal和hidden.bs.modal事件处理程序并在那里调整z-index，可以很容易地达到同样的效果。

下面是一个工作示例

更多信息可以在这里找到。

这个解决方案自动工作于任意深度的堆栈模态。

脚本源代码:

$(document).ready(function() {

    $('.modal').on('hidden.bs.modal', function(event) {
        $(this).removeClass( 'fv-modal-stack' );
        $('body').data( 'fv_open_modals', $('body').data( 'fv_open_modals' ) - 1 );
    });

    $('.modal').on('shown.bs.modal', function (event) {
        // keep track of the number of open modals
        if ( typeof( $('body').data( 'fv_open_modals' ) ) == 'undefined' ) {
            $('body').data( 'fv_open_modals', 0 );
        }

        // if the z-index of this modal has been set, ignore.
        if ($(this).hasClass('fv-modal-stack')) {
            return;
        }

        $(this).addClass('fv-modal-stack');
        $('body').data('fv_open_modals', $('body').data('fv_open_modals' ) + 1 );
        $(this).css('z-index', 1040 + (10 * $('body').data('fv_open_modals' )));
        $('.modal-backdrop').not('.fv-modal-stack').css('z-index', 1039 + (10 * $('body').data('fv_open_modals')));
        $('.modal-backdrop').not('fv-modal-stack').addClass('fv-modal-stack'); 

    });        
});