如何将两个div彼此相邻放置？

Question

    width: 500px;

    border: 1px solid black;

}

#first {

    width: 300px;

    border: 1px solid red;

}

#second {

    border: 1px solid green;

}


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我希望两个div在包装div中彼此相邻。在这种情况下，绿色div的高度应确定包装纸的高度。

我如何通过CSS实现呢？

Answer 1

浮动一个或两个内部div。

浮动一格：

#wrapper {
    width: 500px;
    border: 1px solid black;
    overflow: hidden; /* will contain if #first is longer than #second */
}
#first {
    width: 300px;
    float:left; /* add this */
    border: 1px solid red;
}
#second {
    border: 1px solid green;
    overflow: hidden; /* if you don't want #second to wrap below #first */
}

或者如果您同时浮动两个子元素，则需要鼓励包装器div包含两个浮动子元素，否则它会认为它是空的而不是在它们周围放置边框

浮动两个div：

#wrapper {
    width: 500px;
    border: 1px solid black;
    overflow: hidden; /* add this to contain floated children */
}
#first {
    width: 300px;
    float:left; /* add this */
    border: 1px solid red;
}
#second {
    border: 1px solid green;
    float: left; /* add this */
}