深思 PHP 数组遍历的差异（array_diff 的实现）

'产生不重复随机数
function rndarray(istart,iend,sum)
dim arrayid(),i,j,blnre,temp,iloop,eloop
redim arrayid(sum-1)
i=0
iloop=0
eloop=0
blnre=false
randomize
do while i<sum
temp=int(rnd*(iend-istart+1)+istart)
if i=0 then
arrayid(0)=temp
i=i+1
iloop=iloop+1
else

for j=0 to i-1
if arrayid(j)=temp then
blnre=true
iloop=iloop+1
exit for'这一句很重要，防止多余的循环
else
iloop=iloop+1
end if
next

 if blnre=false then
 arrayid(i)=temp
 i=i+1
 else
 blnre=false
 end if

end if
eloop=eloop+iloop
iloop=0
loop
rndarray=join(arrayid)&"循环次数:"&eloop
end function

response.write rndarray(1,10,5)&"<br>"'调用过程

function rndstr(istart,iend,isum)
dim i,j,vntarray()
redim vntarray(iend-istart)
j=istart
for i=0 to iend-istart
vntarray(i)=j
j=j+1
next

dim vntarray2(),temp,x,y
redim vntarray2(isum-1)
y=iend-istart+1
x=0
temp=vntarray
do while x<isum
dim a
randomize
vntarray2(x)=temp(int(rnd*y))
a=" "&vntarray2(x)&" "
temp=split(trim(replace(chr(32)&join(temp)&chr(32),a," ")))
x=x+1
y=y-1
loop
rndstr=join(vntarray2)
end function

response.write rndstr(1,5,2)