Trigger when button clicked, Getting json data in post call

Trigger when a button is clicked.
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Example of triggering function, on clicking a button
]

on(dom.byId('peerseen'),'click',function(){

                        displayasseen("peer");

                        });

<input type=button id=peerseen data-dojo-type="dijit/form/Button" data-dojo-props="label:'Peer'" />

Using post to get json data

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Example of using post to get data
]

on(dom.byId('processpsybutton'),'click',function(){

                                   request.post("http://localhost/yii/g3labs/?r=Group/processowner").then(
                                               function(data){
                                                ownerpsyrefresh(data);
                                               },

                                                function(err){

                                               }

                                    );