为什么vbscript Mid函数显示错误'无效的过程调用或参数:Mid'

Question

嗨下面是我的ASPClassic代码,其中csvData是一个非常大的字符串,包含variable.Now在此At行中Mid函数调用错误'无效过程调用或参数:Mid'出现为什么会发生这种情况...

Dim dataLen 
    Dim fromLen 
       Dim toLen 
       Dim slab 
       Dim totalPass 

       dataLen =len(csvData)
       fromLen =0
       toLen =100000
       slab =100000
       totalPass =(dataLen/slab)
    if (dataLen Mod slab)>0  then
        totalPass=totalPass+1
    end if
    Dim i
    For i = 0 To dataLen
        i=toLen
        if toLen > dataLen then
            toLen=dataLen
        end if 
       Response.Write Mid(csvData,fromLen,toLen)
        fromLen=toLen
        toLen=toLen+slab
    Next

Answer 1

当你第一次调用Mid()时,我认为你的fromLen是0:

>> m = Mid("x", 0, 1)
>>
Error Number:       5
Error Description:  Invalid procedure call or argument

尝试初始化:

fromLen = 1

Answer 2

mid start位置不能为0,应始终为1