小計算問題

Question

我有一個javascript計算的小問題。我有這樣的功能：

$("#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); 
}); 

但它導致了這一點。任何人都有一個想法如何計算沒有完成？

Position: 722, width: 83, center: NaN 

Answer 1

給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

只是要簡單的修正此線路上。然後你會得到所需的輸出..

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