//测试变量是否为空
function empty(v) {
if(v == false) return true
v = ""+v
var re = / /g
var reArray = v.match(re)
if(reArray)
return (reArray.length==v.length)
v = v+0
if(v==0) return true
return false
}
//返回ch在s中出现的次数
function occur(ch,s) {
s = ""+s
var re = eval("/"+ch+"/gi")
var reArray = s.match(re)
if(reArray)
return reArray.length
return 0
}
//删去首尾空格
function trim(v) {
var re = / *$/
var s = v.replace(re,"")
re =/^ */
return s.replace(re,"")
}