这个作品。这可能是一种粗鄙的方式，但效果很好。它被测试为响应性(Y)。

.centered {
    background-color: teal;
    text-align: center;
}

<div class="container">
    <div class="row row-centered">
        <div class="col-xs-6 col-centered">Column 6</div>
        <div class="col-xs-6 col-centered">Column 6</div>
        <div class="col-xs-3 col-centered">Column 3</div>
        <div class="col-xs-3 col-centered">Column 3</div>
        <div class="col-xs-3 col-centered">Column 3</div>
    </div>
</div>

CSS

/* centered columns styles */
.row-centered {
    text-align:center;
}
.col-centered {
    display:inline-block;
    float:none;
    /* reset the text-align */
    text-align:left;
    /* inline-block space fix */
    margin-right:-4px;
    text-align: center;
    background-color: #ccc;
    border: 1px solid #ddd;
}

Bootstrap版本3有一个.text-center类。

只需添加这个类:

text-center

它只会加载这个样式:

.text-center {
    text-align: center;
}

例子:

<div class="container-fluid">
  <div class="row text-center">
     <div class="col-md-12">
          Bootstrap 4 is coming....
      </div>
  </div>
</div>   

使用bootstrap 4，你可以简单地尝试这里提到的justification -content-md-center

<div class="container">
    <div class="row justify-content-md-center">
        <div class="col col-lg-2">
              1 of 3
        </div>
        <div class="col-md-auto">
            Variable width content
        </div>
        <div class="col col-lg-2">
              3 of 3
        </div>
    </div>
    <div class="row">
        <div class="col">
             1 of 3
        </div>
        <div class="col-md-auto">
                Variable width content
        </div>
        <div class="col col-lg-2">
              3 of 3
        </div>
    </div>
</div>

对于那些当你没有确切的数字来填充你的网格时，希望在屏幕上将列元素居中的人，我写了一小段JavaScript来返回类名:

function colCalculator(totalNumberOfElements, elementsPerRow, screenSize) {
    var arrayFill = function (size, content) {
        return Array.apply(null, Array(size)).map(String.prototype.valueOf, content);
    };

    var elementSize = parseInt(12 / elementsPerRow, 10);
    var normalClassName = 'col-' + screenSize + '-' + elementSize;
    var numberOfFittingElements = parseInt(totalNumberOfElements / elementsPerRow, 10) * elementsPerRow;
    var numberOfRemainingElements = totalNumberOfElements - numberOfFittingElements;
    var ret = arrayFill(numberOfFittingElements, normalClassName);
    var remainingSize = 12 - numberOfRemainingElements * elementSize;
    var remainingLeftSize = parseInt(remainingSize / 2, 10);
    return ret.concat(arrayFill(numberOfRemainingElements, normalClassName + ' col-' + screenSize + '-push-' + remainingLeftSize));
}

如果你有5个元素，你想在md屏幕上每行有3个元素，你可以这样做:

colCalculator(5, 3, 'md')
>> ["col-md-4", "col-md-4", "col-md-4", "col-md-4 col-md-push-2", "col-md-4 col-md-push-2"]

记住，第二个参数必须能被12整除。

使用mx-auto在你的div类使用Bootstrap 4。

<div class="container">
  <div class="row">
    <div class="mx-auto">
      You content here
    </div>
  </div>
</div>