Easyuicombobox three-level linkage

There are a number of problems that have just come into contact with the ComboBox control in Easyui: How to make a ComboBox into a three-level linkage?

First I have a three-level linkage of the case to everyone reference, after testing can pass. Note that the data for the ComboBox binding is in JSON format yo.

$(function () {                varProject1 = $ ("#project1"). ComboBox ({URL:' Project_select.ashx?flg=0 ', Editable:false, Valuefield:' ID ', TextField:' ProjectName ', Editable:false,//do not allow manual entryOnSelect:function(record) {Project2.combobox ({disabled:false, URL:' project_select.ashx?flg= ' +record.id, editable:false, Valuefield:' ID ', TextField:' ProjectName '}). ComboBox (' Clear ');                }                }); varProject2 = $ ("#project2"). ComboBox ({disabled:true, Editable:false, Valuefield:' ID ', TextField:' ProjectName ', OnSelect:function(record) {Project3.combobox ({disabled:false, URL:' project_select.ashx?flg= ' +record.id, editable:false, Valuefield:' ID ', TextField:' ProjectName '}). ComboBox (' Clear ');                }                }); varPROJECT3 = $ ("#project3"). ComboBox ({disabled:true, Editable:false, Valuefield:' ID ', TextField:' ProjectName '                }); });

Easyuicombobox three-level linkage