如何縮短我的jQuery代碼

Question

這是我的代碼。 https://jsfiddle.net/f6m6k0w8/

有沒有更好的方法來縮短下面的代碼而不改變HTML結構？

$(element).parent().prev().children('select[name="custom_type"]').val() 

Answer 1

你可以這樣做：

$(element).closest('.grid_wrap').find('[name="custom_type"]').val() 

DEMO

.closest發現通過其祖先在DOM樹向上遍歷提到最近的元素。所以基本上找到自己closest基地母公司，然後用找得到element

Answer 2

您可以使用.closest()和.map()清理一些代碼

$(function() { 
 
    $('input[type=button]').click(function() { 
 
    var attribute = $('input[name="custom_value"]').map(function(index, element) { 
 
     var row = { 
 
     type: $(element).closest('.grid_wrap').find('select[name="custom_type"]').val(), 
 
     value: element.value 
 
     }; 
 
     return row; 
 
    }).get(); 
 
    $('.result').html(JSON.stringify(attribute)); 
 
    console.log(attribute); 
 
    }); 
 

 
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script> 
 
<p>row 1</p> 
 
<div class="grid_wrap"> 
 
    <div class="grid_row"> 
 
    <select name="custom_type"> 
 
     <option value="A">type A</option> 
 
     <option value="B">type B</option> 
 
     <option value="C">type C</option> 
 
     <option value="D" selected="selected">type D</option> 
 
    </select> 
 
    </div> 
 
    <div class="grid_row"> 
 
    <input type="text" name="custom_value" value="Derrick Rose" /> 
 
    </div> 
 
</div> 
 
<p>row 2</p> 
 
<div class="grid_wrap"> 
 
    <div class="grid_row"> 
 
    <select name="custom_type"> 
 
     <option value="A">type A</option> 
 
     <option value="B">type B</option> 
 
     <option value="C" selected="selected">type C</option> 
 
     <option value="D">type D</option> 
 
    </select> 
 
    </div> 
 
    <div class="grid_row"> 
 
    <input type="text" name="custom_value" value="Camelo Anthony" /> 
 
    </div> 
 
</div> 
 
<p>row 3</p> 
 
<div class="grid_wrap"> 
 
    <div class="grid_row"> 
 
    <select name="custom_type"> 
 
     <option value="A">type A</option> 
 
     <option value="B" selected="selected">type B</option> 
 
     <option value="C">type C</option> 
 
     <option value="D">type D</option> 
 
    </select> 
 
    </div> 
 
    <div class="grid_row"> 
 
    <input type="text" name="custom_value" value="Brandon Roy" /> 
 
    </div> 
 
</div> 
 
<p> 
 
    <input type="button" value="show console" /> 
 
</p> 
 
<div class="result"></div>

Answer 3

的。如果你不僅要短碼，而且優化了的代碼。

當您使用each()循環時，可以使用索引獲取相應的元素值。使用此功能可以避免一些函數調用，如parent(),closest()內部循環來獲取元素值。

$('select[name="custom_type"]').eq(index).val(), 

Demo

此外，檢查優化代碼。

$('input[type=button]').click(function() { 
 
    var attribute = []; 
 

 
    // Cache the elements 
 
    var $customValues = $('select[name="custom_type"]'); 
 

 
    $('input[name="custom_value"]').each(function(index, element) { 
 
    var row = { 
 
     type: $customValues.eq(index).val(), // Get value of corresponding element from cache 
 
     value: element.value 
 
    }; 
 
    attribute.push(row); 
 
    }); 
 
    $('.result').html(JSON.stringify(attribute)); 
 
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script> 
 
<p>row 1</p> 
 
<div class="grid_wrap"> 
 
    <div class="grid_row"> 
 
    <select name="custom_type"> 
 
     <option value="A">type A</option> 
 
     <option value="B">type B</option> 
 
     <option value="C">type C</option> 
 
     <option value="D" selected="selected">type D</option> 
 
    </select> 
 
    </div> 
 
    <div class="grid_row"> 
 
    <input type="text" name="custom_value" value="Derrick Rose" /> 
 
    </div> 
 
</div> 
 
<p>row 2</p> 
 
<div class="grid_wrap"> 
 
    <div class="grid_row"> 
 
    <select name="custom_type"> 
 
     <option value="A">type A</option> 
 
     <option value="B">type B</option> 
 
     <option value="C" selected="selected">type C</option> 
 
     <option value="D">type D</option> 
 
    </select> 
 
    </div> 
 
    <div class="grid_row"> 
 
    <input type="text" name="custom_value" value="Camelo Anthony" /> 
 
    </div> 
 
</div> 
 
<p>row 3</p> 
 
<div class="grid_wrap"> 
 
    <div class="grid_row"> 
 
    <select name="custom_type"> 
 
     <option value="A">type A</option> 
 
     <option value="B" selected="selected">type B</option> 
 
     <option value="C">type C</option> 
 
     <option value="D">type D</option> 
 
    </select> 
 
    </div> 
 
    <div class="grid_row"> 
 
    <input type="text" name="custom_value" value="Brandon Roy" /> 
 
    </div> 
 
</div> 
 
<p> 
 
    <input type="button" value="show console" /> 
 
</p> 
 
<div class="result"></div>