Left, pixelLeft, posLeft, and offsetLeft in JS

Left (string, indicating the & amp; 20540; of left in html) usage: 1. alert (documentgetElementById (& 039; divid & 039;) styleleft) if no value is set, the system returns NULL 2, documentgetElementById (& 039; divid & 039;) styleleft & 039; 100 p left (string, that is, the value of left in html .)
Usage:
1. alert (document. getElementById ('divid'). style. left) // if no value is set, null is returned.
2. document. getElementById ('divid'). style. left = '100px '; // note that the unit is attached.


PixelLeft (numeric type, which converts the left value (0 if it is an empty string) to a pixel value (excluding unit ))
Usage:
1. alert (document. getElementById ('divid'). style. pixelLeft)
2. document. getElementById ('divid'). style. pixelLeft = 100; // This attribute only supports IE


PosLeft (floating point type, which converts the left value (0 if it is an empty string) to a value (without unit ))
Usage:
1. alert (document. getElementById ('divid'). style. posLeft)
2. document. getElementById ('divid'). style. posLeft = 100; // This attribute only supports IE


OffsetLeft (the offset of an element relative to its parent element. If no parent element is located, it is relative to the page .)
Usage:
1. alert (document. getElementById ('divid'). offsetLeft) // return a value


Jquery1.2 and later support: $ ("# divid"). offset (). left
Usage:
1. alert ($ ("# divid"). offset (). left)