<input id="txtPipeRowName" style="width:150px;">    
<input id="txtPipeName" style="width:150px;"> 

// 一层Combo 
var srmCombx = $("#txtShouName")combobox({ 
loader:function(param,success,error){ 
  $ajax({ 
url: '${CTX_ROOT}/TEquipmentsController?method=getEquipmentByParId&id='+selectSgId+'', 
dataType: 'json', 
success: function(data){ 
dataunshift({equipmentid:'',equipmentname:'全部'}); 
success(data); 
}, 
        error: function(){ 
errorapply(this, arguments); 
} 
}); 
  }, 
  onSelect:function(record){ //onSelect 用户点击时触发的事件 在此的意义在于，用户点击一级后自动二级combobox 
  piperowCombxcombobox({ 
loader:function(param,success,error){ 
  $ajax({ 
url: '${CTX_ROOT}/TEquipmentsController?method=getEquipmentByParId&id='+$("#txtShouName")combobox("getValue")+'', 
dataType: 'json', 
success: function(data){ 
dataunshift({equipmentid:'',equipmentname:'全部'}); 
success(data); 
}, 
        error: function(){ 
errorapply(this, arguments); 
} 
}); 
  }, 
  onSelect:function(record){ //这里也使用了onSelect事件，在二级combobox被用户点击时触发三级combobox 
  pipeCombxcombobox({ 
loader:function(param,success,error){ 
  $ajax({ 
url: '${CTX_ROOT}/TEquipmentsController?method=getEquipmentByParId&id='+$("#txtPipeRowName")combobox("getValue")+'', 
dataType: 'json', 
success: function(data){ 
dataunshift({equipmentid:'',equipmentname:'全部'}); 
success(data); 
}, 
        error: function(){ 
errorapply(this, arguments); 
} 
}); 
  }, 
  valueField: 'equipmentid',   
  textField: 'equipmentname', 
  value:'', 
  editable:false 
}); 
  }, 
  onLoadSuccess:function(){ //清空三级下拉框 就是成功加载完触发的事件 当一级combobox改变时，二级和三级就需要清空 
  pipeCombxcombobox("clear"); 
  pipeCombxcombobox('setValue', '全部'); //给combobox下拉框设置一个值，否则为空不好看 
  }, 
  valueField: 'equipmentid',   
  textField: 'equipmentname', 
  value:'', 
  editable:false 
})combobox("clear"); //清空二级下拉框 
 
  }, 
  valueField: 'equipmentid',   
  textField: 'equipmentname', 
  value:'', 
  editable:false 
}); 
/*******************************/ 
//下面的俩个是组件， 
 
// 二层Combo 
var piperowCombx = $("#txtPipeRowName")combobox({ 
loader:function(param,success,error){ 
  $ajax({ 
url: '${CTX_ROOT}/TEquipmentsController?method=getEquipmentByParId&id='+$("#txtShouName")combobox("getValue")+'', 
dataType: 'json', 
success: function(data){ 
dataunshift({equipmentid:'',equipmentname:'全部'}); 
success(data); 
}, 
        error: function(){ 
errorapply(this, arguments); 
} 
}); 
  }, 
  valueField: 'equipmentid',   
  textField: 'equipmentname', 
  value:'', 
  editable:false 
}); 
 
//三层Combo 
var pipeCombx=$("#txtPipeName")combobox({ 
loader:function(param,success,error){ 
  $ajax({ 
url: '${CTX_ROOT}/TEquipmentsController?method=getEquipmentByParId&id='+$("#txtPipeRowName")combobox("getValue")+'', 
dataType: 'json', 
success: function(data){ 
dataunshift({equipmentid:'',equipmentname:'全部'}); 
success(data); 
}, 
        error: function(){ 
errorapply(this, arguments); 
} 
}); 
  }, 
  valueField: 'equipmentid',   
  textField: 'equipmentname', 
  value:'', 
  editable:false 
});