How to use $.getJSON() method of jQuery with grails?

Retriving a JSON string from Grails is very easy. You have to just write the following in your controller’s action

Let me explain you with an example of populating a HTML table using JSON response:
In this example, we have table with columns – name,address and gender. We want the table to be populated without doing a full page refresh, using an Ajax call.

Domain Class:

class MyDomain {
    String name
    String address
    String gender
}

Controller Class :

class MyController {
   def someaction = {
      List myDomains = MyDomain.findAllByGender(params.gender)
      <em>/*Let say 5 objects are retrieved*/</em>
      render myDomains as JSON
   }
}

The above code in action will render a JSON string in the following format:

[
{
"name" : "John",
"address" : "New York",
"gender" : "Male"
},
{
"name" : "Rob",
"address" : "Indonasia",
"gender" : "Male"
},
{
"name" : "Shayam",
"address" : "New Delhi",
"gender" : "Male"
},
{
"name" : "Chang",
"address" : "Thailand",
"gender" : "Male"
},
{
"name" : "Ali",
"address" : "London",
"gender" : "Male"
}
]

following script would be writtent on the client Side (in the GSP):

<script>
$.document.ready(function(){
$('#someid').click(function(){
<strong>$.getJSON</strong>("${createLink(controller:'my',action:'someaction')}",{gender:'Male', ajax: 'true'}, function(myDomains){
var myHTMLString = ''
for(var i = 0 ; i < myDomains.length ; i++)
{
myHTMLString = myHTMLString + '<tr><td>' + myDomains[i].name + '</td>'
myHTMLString = myHTMLString + '<tr><td>' + myDomains[i].address + '</td>'
myHTMLString = myHTMLString + '<tr><td>' + myDomains[i].gender + '</td></tr>'
}
$('table#mytable').html(myHTMLString)
})
})
})
</script>

The HTML code would be like this :

<div id=”someid”>
Click for JSON Response
</div>
<table id=”mytable”>
<!–empty table –>
</table>

When you click on the displayed text the html page would become like following:

<div id="someid">
Click for JSON Response
</div>
<table id="mytable">
<tr>
<td>John</td>
<td>New York</td>
<td>Male</td>
</tr>
<tr>
<td>Rob</td>
<td>Indonasia</td>
<td>Male</td>
</tr>
<tr>
<td>Shayam</td>
<td>New Delhi</td>
<td>Male</td>
</tr>
<tr>
<td>Chang</td>
<td>Thailand</td>
<td>Male</td>
</tr>
<tr>
<td>Ali</td>
<td>London</td>
<td>Male</td>
</tr>
</table>

any kind of suggestions and comments are welcome……

Regards,
Chandan Luthra

http://www.IntelliGrape.com