小计算问题

Question

我有一个javascript计算的小问题。我有这样的功能：

$("#main-nav li[class]").each(function(index) { 
    var position = $(this).offset(); 
    var width = $(this).width(); 
    var center = parseInt(position) - (parseInt(width)/2); 
    console.log("Position: " + position.left + ", width: " + width + ", center: " + center); 
}); 

但它导致了这一点。任何人都有一个想法如何计算没有完成？

Position: 722, width: 83, center: NaN 

Answer 1

给position.left

$("#main-nav li[class]").each(function(index) { 
    var position = $(this).offset(); 
    var width = $(this).width(); 
    var center = parseInt(position.left) - (parseInt(width)/2); 
    console.log("Position: " + position.left + ", width: " + width + ", center: " + center); 
}); 

Answer 2

只是要简单的修正此线路上。然后你会得到所需的输出..

var center = parseInt(position.left) - (parseInt(width)/2);