unwanted characters warning.

struth · Mar 6, 2006

I trying to prevent the uploading of files which include any character of ther than 1-9 and a-z ... but it isn't quite working.

function checkUploadString(str) {
checkStr = FilenameOnly(str);
var ValidString = "01234567890abcdefghilklmnop qrstuvABCDEFGHIJKLMNOPQRSTUVWXYZ";
var Ret = allowInString(checkStr, ValidString);
if (Ret = true){
alert("Sorry can't upload this file /n Please rename it using only letters a-z and 0-9");
return(false);
}
}

function allowInString (InString, RefString) {
if(InString.length==0) return (false);
for (Count=0; Count < InString.length; Count++) {
TempChar= InString.substring (Count, Count+1);
if (RefString.indexOf (TempChar, 0)==-1)
return (false);
}
return (true);
}

function FilenameOnly (InString) {
LastSlash=InString.lastIndexOf ('\\', InString.length-1)
OutString=InString.substring (LastSlash+1, InString.length)
return (OutString);
}

Where am I going wrong?
TIA

Away from the actual ... everything is virtual

cLFlaVA · Mar 6, 2006

without looking too deep into your code, i noticed this:

Code:

if (Ret = true){

which should be:

Code:

if (Ret =[red]=[/red] true){

if you change that, does it work ok?

*cLFlaVA
----------------------------
[tt]( )[sup]13[/sup] * ( <.)[/tt]

[URL unfurl="true"]http://www.coryarthus.com/[/url]

struth · Mar 6, 2006

Thanks cLFlaVA ... I have made this mistake before but on this occasion, I've tried it and it makes no difference.

Away from the actual ... everything is virtual

kaht · Mar 6, 2006

Another thing - try using regular expressions when doing string validation. They'll cut your code down extensively. The function you wrote is an easy 1-liner with regexp, so there's no need to reinvent the wheel. Also, when checking for equality to a boolean value, you don't have to put the ==true part, it's implied. To do ==false you only have to add a ! to the beginning of the expression.

Code:

function checkUploadString(str) {
    checkStr = FilenameOnly(str);
    var Ret = [!]/[^A-Za-z0-9 ]/g.test(checkStr);[/!]
    if ([!]!Ret[/!]) {
       alert("Sorry can't upload this file /n Please rename it using only letters a-z and 0-9");
       return(false);
    }
}

-kaht

[small] <.[/small]
[banghead]

[small](He's back)[/small]

struth · Mar 6, 2006

Thanks kaht. I was having problems getting your regexp to work so I did this little test thing. But still it did not work smoothly as I got not no alert on checkBad and a 'no problem' alert on testGood even if I introduced bad characters like 'ok%& doc.doc'. Have I got it wrong in removing the '!' before 'Ret' on testGood?

Code:

<HTML>
<HEAD>
<TITLE>Unwanted characters test Test</TITLE>
<SCRIPT LANGUAGE="JavaScript">
function checkGood() {
    checkStr = 'C:\My documents\test docs\ok doc.doc';
    var Ret = /[^A-Za-z0-9 ]/g.test(checkStr);
    if (Ret) {
       alert("no problem");
       return(false);
    }
}

function checkBad() {
    checkStr = 'C:\My documents\test docs\bad%73$’#.doc';
    var Ret = /[^A-Za-z0-9 ]/g.test(checkStr);
    if (!Ret) {
       alert("Sorry can't upload this file \n Please rename it using only letters a-z and 0-9");
       return(false);
    }
}
</SCRIPT>
<BODY>
<FORM>
<INPUT TYPE="button" VALUE="Check good" onClick="checkGood()">
<INPUT TYPE="button" VALUE="Check bad" onClick="checkBad()">
</FORM>
</BODY>
</HTML>

Away from the actual ... everything is virtual

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unwanted characters warning.

struth

Programmer

cLFlaVA

Programmer

struth

Programmer

kaht

Programmer

struth

Programmer

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