如何在jquery上運行if-else語句？

Question

我有下面的代碼。現在我想運行一個if-else語句，但它不起作用。有這個想法嗎？

var num1 = $('#id1').val(); 
var num2 = $('#id2').val(); 

var newVal = (num1+2)*(num2/4); 
var nextVal =(num1+4)*(num2/2); 
var newArr = new Array(); 
newArr.push(newVal); 
newArr.push(nextVal); 

newArr.sort(); 

if(newArr.get(0)==newVal) 
$("body").html("<p>works fine!</p>"); 
else $("body").html("<p>works awfully!</p>"); 

Answer 1

你宣稱 「無功」 與資本V，而這條線：

Var newVal = (num1+2)*(num2/4); 

此外，訪問數組[索引]的元素，而不是不用彷徨（index）

這裏是編輯代碼：

var num1 = 50; 
    var num2 = 100; 

    var newVal = parseInt((num1+2)*(num2/4)); 
    var nextVal =parseInt((num1+4)*(num2/2)); 
    var newArr = new Array(); 
    newArr.push(newVal); 
    newArr.push(nextVal); 

    newArr = newArr.sort(function(a,b){return a - b}); 

    if(newArr[0]==newVal) 
    $("body").html("<p>works fine!</p>"); 
    else 
    $("body").html("<p>works awfully!</p>");​ 

Answer 2

只需使用newArr[0]代替newArr.get(0)

Answer 3

試試這個

var num1 = 50; 
    var num2 = 100; 

    var newVal = (num1+2)*(num2/4); 
    var nextVal =(num1+4)*(num2/2); 
    var newArr = new Array(); 
    newArr.push(newVal); 
    newArr.push(nextVal); 

    newArr.sort(); 

    if(newArr[0]==newVal) 
    $("body").html("<p>works fine!</p>"); 
    else 
    $("body").html("<p>works awfully!</p>"); 

Answer 4

val將返回一個字符串，所以你可能要轉換爲數字。您可以使用一元加運算符：

var num1 = +$('#id1').val(); // Now you get 5 instead of "5" 
var num2 = +$('#id2').val(); 

//The problem shows up here when you are doing string concatenation instead of addition in the first set of parenthesis 
var newVal = (num1+2)*(num2/4); 

if(newArr[0]==newVal) // .get is for jQuery collections, just use brackets on an array