看看这两种办法,是用不同的方法。http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=uV9zdJkMCHA.2392%40tkmsftngp04&rnum=2&prev=/groups%3Fhl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26selm%3DuV9zdJkMCHA.2392%2540tkmsftngp04%26rnum%3D2http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&threadm=rsFZSGsYCHA.1664%40cpmsftngxa06&rnum=1&prev=/groups%3Fhl%3Den%26lr%3D%26ie%3DUTF-8%26oe%3DUTF-8%26selm%3DrsFZSGsYCHA.1664%2540cpmsftngxa06