[{  
  "id":1,  
  "text":"text1"  
},{  
  "id":2,  
  "text":"text2"  
},{  
  "id":3,  
  "text":"text3",  
  "selected":true  
},{  
  "id":4,  
  "text":"text4"  
},{  
  "id":5,  
  "text":"text5"  
}]

<select id="in_edit_netlink" style="width:160px;" class="easyui-combobox" data-options="valueField:'id',textField:'text',editable:false" >
</select>

var ljfsArray = new Array();
  var objHTTP = new Object();
  objHTTP.text = "HTTP";
  var objTCP = new Object();
  objTCP.text = "TCP";
  objTCP.id = 1;
  objHTTP.id = 2;
  if (data.ljfs == "HTTP") {
    objHTTP.selected=true;
  } else {
    objTCP.selected=true;
  }
  ljfsArray.push(objHTTP);
  ljfsArray.push(objTCP);
  $('#in_edit_netlink').combobox('loadData', ljfsArray);

$("#in_edit_netlink").combobox({
    onSelect: function () {
      connectionType = $('#in_edit_netlink').val();
      if (connectionType == 1) {
       $('#in_edit_sjjh').textbox('setValue', tcpIp);
      } else {
       $('#in_edit_sjjh').textbox('setValue', httpIp);
      }
    }
  })

$(function () {
  
})