jqgrid select box option set selected

i am using jqgrid and i am adding a row that contains fields: textbox and selectbox.

After adding a row by selecting the age from the dropdown, when i click on this row for editing, the age dropdown list must mark the selected value by default. How to achieve this ?

This is the code showing the columns data:

colModel:[                          
{name:'user_id',index:'user_id',  width:150,align:"center",editable:false,editoptions:{readonl开发者_运维知识库y:true,size:10}},      
{name:'user_name',index:'user_name', width:250, align:"left",editable:true,editoptions:{size:30}},
{name: 'Age', width: 40, editable: true, formatter: 'select',
edittype: 'select', editoptions: { value: age_list },   
hidden: true, editrules: { edithidden: true }}
]

where 'age_list' is the array of age values in the form of a javascript array.

Use edittype: 'custom' for your column, and then you can create your own html for the control:

<script>
jQuery("#grid_id").jqGrid({
...
   colModel: [ 
      ... 
      {name:'price', ..., editable:true, edittype:'custom', editoptions:{custom_element: functionThatReturnsHtmlElement, custom_value: functionThatReturnsTheValueYouNeed} },
      ...
   ]
...
});
</script>

More details at jqGrid's documentation wiki: http://www.trirand.com/jqgridwiki/doku.php?id=wiki:common_rules#editable