否則，如果在JavaScript

Question

我想根據用戶輸入來計算一個字符串，並顯示一些消息：

$('#myInput').keyup(function() { 
    if(this.value.length<=158) 
    $('#charCount').text('We will deduct 1 credit from your account'); 
    else if(this.value.length>158 || this.value.length<316) 
     $('#charCount').text('We will deduct 2 credit from your account'); 
    else if(this.value.length>316 || this.value.length<400) 
     $('#charCount').text('We will deduct 3 credit from your account'); 
}); 

http://jsfiddle.net/p9jVB/11/

的問題是最後else if是不工作...我有錯過了什麼？

Answer 1

它看起來像你的意思是& &，而不是||

$('#myInput').keyup(function() { 
    if(this.value.length<=158) 
     $('#charCount').text('We will deduct 1 credit from your account'); 
    else if(this.value.length>158 && this.value.length<=316) 
     $('#charCount').text('We will deduct 2 credit from your account'); 
    else if(this.value.length>316 && this.value.length<400) 
     $('#charCount').text('We will deduct 3 credit from your account'); 
}); 

Answer 2

else if(this.value.length>158 || this.value.length<316) 
    $('#charCount').text('We will deduct 2 credit from your account'); 
else if(this.value.length>316 || this.value.length<400) 
    $('#charCount').text('We will deduct 3 credit from your account'); 

在世界上每一個數字比316小大於158 或，所以替代條件將永遠不會達到。