var dt_columns=[
{ key: "check", formatter:"checkbox"},
{ key: "status_name", formatter:"dropdown",dropdownOptions:[{"text":"Connection.Threads_connected","value":"1012"},{"text":"Connection.Threads_running","value":"1013"},{"text":"Fullscan.Select_full_join","value":"1023"},{"text":"Fullscan.Select_full_range_join","value":"1024"}]},
{ key: "start_date", editor:"textbox"},
{ key: "end_date", editor:"textbox"},
{ key: "data_type", formatter:"dropdown",dropdownOptions:["day_sum","day_max","night_sum","night_max"] },
{ key: "Top_N", editor:"textbox" }
];

今天看了一下源码知道dropdownOptions分开定义一个option的value和text部分。如红色部分。
如果想value和text相同，像蓝色部分那样定义就行了。

JS真是灵活。YUI写的真是不错