DropDownList二级级联

<script>  

    function onCommandInputPropertyChange(){  

        if (event.propertyName == "value"){  

            var cmdInput = event.srcElement;  

            if (cmdInput.value != 0){  

                //alert(cmdInput.value);  

        BindRoleName(cmdInput.value);        

            }  

        }  

    }  

    //绑定角色名  

    function BindRoleName(RoleID){  

    //SysBase_UserEdit是aspx页面的名称  

        SysBase_UserEdit.getRoleData(RoleID,get_AllName);  

    }  

    function get_AllName(response){  

        var AllName = document.getElementById("DDLAjax");  

        AllName.length = 0;  

        if (response.value != null){   

            var ds = response.value;  

            if(ds != null && typeof(ds) == "object"){             

                var name = ds.Tables[0].Rows[0].rolename;  

            var id = ds.Tables[0].Rows[0].id;             

            AllName.options.add(new Option(name,id));  

        }  

    }  

    }  

</script>