${if(lev = '0'){switch(srch,'a'," select from",'b'," select from",'c'," select from")} if(lev = '1'){switch(srch,'a',"select from ",'b'," select from",'c'," select from")} if(lev = '2'){switch(srch,'b'," select from",'c'," select from")} if(lev = '3'){switch(srch,'c'," select from ")}}以上有两个switch或者一个if+一个switch