在Rails中使用select_month時獲得空白選項

Question

我無法在Rails中獲取date_select標籤以顯示空白選項。這是我的代碼：

<%= select_month(@foo, :include_blank => true) %> 

但是，該代碼呈現此HTML沒有空白選項。

<select id="month" name="month"><option value="1">January</option> 
    <option value="2">February</option> 

    <option value="3">March</option> 
    <option value="4">April</option> 
    <option value="5">May</option> 
    <option value="6">June</option> 
    <option value="7">July</option> 
    <option value="8">August</option> 
    <option value="9">September</option> 
    <option value="10">October</option> 
    <option value="11">November</option> 

    <option value="12">December</option> 
</select> 

我可以忽略一些東西嗎？

Answer 1

您正在使用哪種版本的導軌？我剛剛在控制檯（Rails 3.0.8）中試過，它的工作原理如下：

ruby-1.9.2-p0 > include ActionView::Helpers::DateHelper 
ruby-1.9.2-p0 > select_month(Time.now) 

=> <select id="date_month" name="date[month]"> 
<option value="1">January</option> 
<option value="2">February</option> 
<option value="3">March</option> 
<option value="4">April</option> 
<option value="5">May</option> 
<option value="6">June</option> 
<option selected="selected" value="7">July</option> 
<option value="8">August</option> 
<option value="9">September</option> 
<option value="10">October</option> 
<option value="11">November</option> 
<option value="12">December</option> 
</select> 

ruby-1.9.2-p0 > select_month(Time.now, :include_blank => true) 
=> <select id="date_month" name="date[month]"> 
<option value=""></option> 
<option value="1">January</option> 
<option value="2">February</option> 
<option value="3">March</option> 
<option value="4">April</option> 
<option value="5">May</option> 
<option value="6">June</option> 
<option selected="selected" value="7">July</option> 
<option value="8">August</option> 
<option value="9">September</option> 
<option value="10">October</option> 
<option value="11">November</option> 
<option value="12">December</option> 
</select>