Question

有什麼方法可以將字符串轉換爲Javascript中的變量？現在，我有什麼是基於選擇框的值更新數據的腳本：

<script type="text/javascript"> 
var a = new Array(); 
a[0] = 'Name'; 
a[1] = 'Description'; 

var b = new Array(); 
b[0] = 'Name 2'; 
b[1] = 'Description 2'; 

function changeSystem(){ 
    var selectedAccount=document.getElementById('selected_option').value; 

    document.getElementById('name').innerHTML = selectedAccount[0]; 
    document.getElementById('description').innerHTML = selectedAccount[1]; 
} 
</script> 
<form method="POST"> 
    <select onchange="changeSystem()" id="selected_option"> 
    <option>A</option> 
    <option>B</option> 
    </select> 
</form> 
<span id="name"></span><br> 
<span id="description"></span><br> 

selectedAccount是<select>所選元素的字符串。但是，要訪問該陣列，它需要是一個變量，即a[0]而不是'a'[0]。這有什麼解決方案？

Answer 1

var dict = { 
    'A': ['Name', 'Description'], 
    'B': ['Name 2', 'Description'] 
}; 

dict['A'][0] 

所以，動態地

dict[selectedAccount][0] 

訪問您可以使用對象文本而不是數組：

var dict = { 
    'A': {'name': 'john'} 
}; 

dict['A']['name'] 

Answer 2

我會使用類似的東西：

<script type="text/javascript"> 
var stuff = { 
    A: { name: 'Name', desc: 'Description'}, 
    B: { name: 'Name 2', desc: 'Description 2'} 
}; 

function $(aId) { 
    return document.getElementById(aId); 
} 

function changeSystem(){ 
    var selectedAccount = $('selected_option').value; 

    if (selectedAccount in stuff) { 
     $('name').innerHTML = stuff[selectedAccount].name; 
     $('description').innerHTML = stuff[selectedAccount].desc; 
    } else { 
     $('name').innerHTML = ''; 
     $('description').innerHTML = ''; 
    } 
} 
</script> 
<form method="POST"> 
    <select onchange="changeSystem()" id="selected_option"> 
     <option>A</option> 
     <option>B</option> 
     <option>C</option> 
    </select> 
</form> 
<span id="name"></span><br> 
<span id="description"></span><br> 

測試日期：Google Chrome 6.0.427.0 de v