这就是我成功的秘诀:

@media only screen and (min-width:769px) and (max-width:1000px){
.navbar-collapse.collapse {
    display: none !important;
}
.navbar-collapse.collapse.in {
    display: block !important;
}
.navbar-header .collapse, .navbar-toggle {
    display:block !important;
}

在bootstrap v4中，导航可以迟早使用不同的css类进行折叠

eg:

导航栏-切换-SM 导航栏-切换-MD 导航栏-切换-LG

导航按钮:

hidden-sm-up hidden-md-up hidden-lg-up

这就是我成功的秘诀:

@media only screen and (min-width:769px) and (max-width:1000px){
.navbar-collapse.collapse {
    display: none !important;
}
.navbar-collapse.collapse.in {
    display: block !important;
}
.navbar-header .collapse, .navbar-toggle {
    display:block !important;
}

在Bootstrap 3 . less源代码中，变量中定义了一个变量。Less被称为@grid-float-breakpoint，它有以下有用的评论:

//**Point at which the navbar becomes uncollapsed
@grid-float-breakpoint: @screen-sm-min;

匹配的@grid-float-breakpoint-max值设置为- 1px:

//**Point at which the navbar begins collapsing
@grid-float-breakpoint-max: (@grid-float-breakpoint-max - 1);

解决方案:

所以只需将@grid-float-breakpoint的值设置为1000px，然后重新构建bootstrap。较少进入bootstrap.css:

e.g.

@grid-float-breakpoint: 1000px;

除了@Skely answer，要使导航栏内的下拉菜单工作，也添加他们的类被覆盖。最终代码如下:

    @media (min-width: 768px) and (max-width: 991px) {
        .navbar-nav .open .dropdown-menu {
            position: static;
            float: none;
            width: auto;
            margin-top: 0;
            background-color: transparent;
            border: 0;
            -webkit-box-shadow: none;
            box-shadow: none;
        }
        .navbar-nav .open .dropdown-menu > li > a {
            line-height: 20px;
        }
        .navbar-nav .open .dropdown-menu > li > a,
        .navbar-nav .open .dropdown-menu .dropdown-header {
            padding: 5px 15px 5px 25px;
        }
        .dropdown-menu > li > a {
            display: block;
            padding: 3px 20px;
            clear: both;
            font-weight: normal;
            line-height: 1.42857143;
            color: #333;
            white-space: nowrap;
        }
        .navbar-header {
            float: none;
        }
        .navbar-toggle {
            display: block;
        }
        .navbar-collapse {
            border-top: 1px solid transparent;
            box-shadow: inset 0 1px 0 rgba(255,255,255,0.1);
        }
        .navbar-collapse.collapse {
            display: none!important;
        }
        .navbar-nav {
            float: none!important;
            /*margin: 7.5px -15px;*/
            margin: 7.5px 50px 7.5px -15px
        }
        .navbar-nav>li {
            float: none;
        }
        .navbar-nav>li>a {
            padding-top: 10px;
            padding-bottom: 10px;
        }
        .navbar-text {
            float: none;
            margin: 15px 0;
        }
        /* since 3.1.0 */
        .navbar-collapse.collapse.in { 
            display: block!important;
        }
        .collapsing {
            overflow: hidden!important;
        }
    }

演示代码

Sass改变引导变量的方法实际上在bootstrap- Sass github页面上有文档。

只需在@import bootstrap之前重新定义变量:

$grid-float-breakpoint: 1000px;

@import 'bootstrap';