翻译ASP功能

Question

Can someone that is familiar with VB Script and ASP have a quick look at this function and tell me what it does so I can translate it to PHP? The beginning I can translate just fine, it's the for loop that it has. That's where I'm not sure what the code is doing exactly. The best I can do by looking at it is that it's going through the string strTemp it's creating a new sum adding the value of each digit. Thanks.

Function CheckSum (strTemp)
Dim i, intTemp

If Not IsNumeric(strTemp) Then
    CheckSum = 0
    Exit Function
End If

intTemp = 0

For i = 1 To Len(strTemp)
    intTemp = intTemp + CInt(Mid(strTemp, i, 1))
Next

CheckSum = intTemp
End Function

Answer 1

Yes, you are correct - it is going through the string strTemp and summing the value of each digit. The function returns this 'checksum' value.

Note that for this to work properly string will always have to digits 0-9 only, which ties up with the check near the top of the function.