<%= simple_form_for @product, method: :post, url: save_item_path do |f| %>
<tr>
<td>
Category
</td>
<td>
<%= f.input :category_id, collection: Category.all, label: false, prompt: 'Select your category', required: true ,required: true %>
</td>
</tr>
<div class="row " style="height:100px;width:100%">
<div class="col-md-5 sub-cat-dropdown">
<select class="select required sub-cat" required="required" name="product[sub_id]"><option value="">Select your sub category</option><option value="15">Bottle</option><option value="16">Charger</option></select>
</div>
</div>
<div class="row">
<div class="col-md-3 col-md-offset-5">
<%= f.submit :submit %>
</div>
</div>
<% end %>
表格将与所有需要的参数一起提交.这里是参数
{"utf8"=>"✓", "authenticity_token"=>"4gY7lWgSqo6j4UoZ78iv1nsaMq9TUXLXE2oQzlqqyh3I3oED3CxwM04cB1n5P+Nz81O3Vvk+/NDPxixNey/J9Q==", "product"=>{"name"=>"vamsi", "price"=>"456", "availability"=>"true", "about"=>"aerg", "ref"=>"456", "texture"=>"rdgg", "shipping"=>"ewataewrg", "category_id"=>"13", "notes"=>"feartg", "packaging"=>"wer5tyy", "sub_id"=>"15"}, "commit"=>"submit", "controller"=>"items", "action"=>"create"}
在上面的params哈希中,你可以提交sub_id.
但是,必须根据主类别的选择动态生成子类别下拉列表.
所以sub-cat-dropdown div就像这样清空了
<div class="row " style="height:100px;width:100%">
<div class="col-md-5 sub-cat-dropdown">
</div>
</div>
我想点击主要类别下拉列表,在子猫下拉列表中注入一个选择标记
这是我写的代码
$(document).ready(function(){
//this function is supposed to create a dropdown of sub category
//based on the main category dropdown
$('#product_category_id').on('change', function(){
var values = [];
var inner_contents = [];
if(this.value === undefined){
return;
}else{
$main_category = this.value;
$main_category_length = $cat_obj[$main_category].length;
for (var i=0;i<$main_category_length;i++){
values.push($cat_obj[$main_category][i].id);
inner_contents.push($cat_obj[$main_category][i].name);
}
$('.sub-cat-dropdown').empty();
inject_sub_category(values, inner_contents);
}
});
// this function injects a dropdown of sub categories, just below the categories ...
function inject_sub_category(value_array, inner_html_array){
var select = document.createElement("select");
select.setAttribute("class","select required sub-cat");
select.setAttribute("required","required");
select.setAttribute("name","sub_id");
// the above will create this
// <select class ="select required form-control"
// required = "required"
// name = "product[sub_id]"
// id = "sub_cat_id">
// </select>
$('.sub-cat-dropdown').append(select);
// setting the default option
var default_option = document.createElement("option");
default_option.setAttribute("value","")
default_option.innerHTML = default_option.innerHTML + "Select your sub category";
select.appendChild(default_option);
// injecting <option value> Select your category </option> under select tag
// creating options of subcategories, and injecting under the select element as children
for(var i = 0 ; i< value_array.length ; i++){
var option_element = document.createElement("option");
option_element.setAttribute("value",value_array[i]);
option_element.innerHTML = option_element.innerHTML + inner_html_array[i];
select.appendChild(option_element)
}
}
// this is supposed to read the json data of the categories and sub categories
$.ajax({
url: "http://localhost:3000/categories_api/show",
type: 'GET',
dataType: 'json',
success: function(res) {
$cat_obj = res;
}
});
});
上面代码的作用是它应该在子猫下拉列表中插入一个选择下拉列表
插入的选择标记看起来像这样,从浏览器复制
<div class="col-md-5 sub-cat-dropdown" style="-webkit-user-select: text;"><select class="select required sub-cat" required="required" name="product[sub_id]"><option value="">Select your sub category</option><option value="15">Bottle</option><option value="16">Charger</option></select></div>
但是,当表单提交发生时,params没有sub_id
{"utf8"=>"✓", "authenticity_token"=>"zUVF55KdvQ4l8nBjtlIcofqHECgd3/pIi7U97cF0xbrnnf9xJqNns8gPPSOgpVAEcs6V0bewdE9XGQFu4PHGUg==", "product"=>{"name"=>"jdkrfb", "price"=>"89", "availability"=>"true", "about"=>"sfukb", "ref"=>"78678", "texture"=>"jkdfbjkrbg", "shipping"=>"jkdfsk", "category_id"=>"12", "notes"=>"jhhdfvbj", "packaging"=>"sajkf"}, "commit"=>"submit", "controller"=>"items", "action"=>"create"}
我在过去几个小时内遇到过这个问题,我们将非常感谢您的帮助.
我的观察：
ajax调用和生成select标记的函数没有问题.我可以看到DOM具有生成的选择标记,并且是子猫下拉列表的子项.
静态选择标记的sub_id正在提交,但对于动态标记,则不是这样.它没有提交
最佳答案 在javascript中,即使您在DOM中看到它们,也无法在动态创建的元素上添加事件侦听器.这就是为什么动态创建的选择选项输入将在DOM中但不包含在表单数据中.尝试将选择输入保持为静态并使其中的选项保持动态.
<div class="row " style="height:100px;width:100%">
<div class="col-md-5 sub-cat-dropdown">
<select class="select required form-control" required="required" name="product[sub_id]" id="sub_cat_id">
</select>
</div>
</div>
代替
<div class="row " style="height:100px;width:100%">
<div class="col-md-5 sub-cat-dropdown">
</div>
</div>
然后通过javascript更改选择输入内的选项 –
function inject_sub_category(value_array, inner_html_array){
// setting the default option
var default_option = document.createElement("option");
default_option.setAttribute("value","")
default_option.innerHTML = default_option.innerHTML + "Select your sub category";
$("#sub_cat_id").append(default_option);
// injecting <option value> Select your category </option> under select tag
// creating options of subcategories, and injecting under the select element as children
for(var i = 0 ; i< value_array.length ; i++){
var option_element = document.createElement("option");
option_element.setAttribute("value",value_array[i]);
option_element.innerHTML = option_element.innerHTML + inner_html_array[i];
$("#sub_cat_id").append(option_element)
}
}
还有另一种使用event delegation的方法.
