The pure js Code enables the vertical and horizontal center display of elements with unknown width and height in the specified element, and the js Element

The pure js Code enables the vertical and horizontal center display of elements with unknown width and height in the specified element, and the js Element

The following uses the span element as an example to describe howImplement the horizontal vertical center effect of the span element in the divThe Code is as follows:

<! DOCTYPE html> 
The above code implements the vertical and horizontal center effect of the span element in the div. The following describes the implementation process of the span element.

I. Implementation principle:

Although css clearly defines the size of the span element, it has a size after all. this size can be obtained using the offsetWidth and offsetHeight attributes, and then the span element is set to absolute positioning, then, set the left and top attribute values to 50% respectively, but this is not the center point vertical and horizontal center of the span element, but the vertical and horizontal center of the upper left corner of the span element, then, when the negative margin of the span element is set, the size is half the width and height of the span element. This achieves the vertical and horizontal center effect.
The above is all the content of this article. We will update the Usage Details of attributes such as scrollTop, offsetHeight, and offsetTop in the future. Please stay tuned to this site. Thank you.