compare multiple form elements for duplicate info

[ibjdt]

i have a form with 5 document attachment fields (upload1, upload2...upload5).

onSubmit i would like to compare the value of all 5 fields and alert the user if they have selected the same file 2+ times (as defined by the form field contents being identical in multiple fields).

a min of 1 upload is required, so there could be as many as 4 blank attachment fields. the js comparison would have to disregard blank elements - which would show as identical and give an error.

thanks.

 

[cLFlaVA]

what do you have so far? this question reads like a requirements document. we're here to help you in finding problems with your code -- not to write code for you.

have you tried anything so far? if so, what have you got? we'd be glad to help.



*cLFlaVA
----------------------------
[tt]"quote goes here"[/tt]
[URL unfurl="true"]http://www.coryarthus.com/[/url]

 

[ibjdt]

i started the obvious manual loop approach:

	if (upload1 == upload2 || upload3 || upload4 || upload5)
	{
		missinginfo += "\n     -  Duplicate Attachments Selected";
		duplicates++;
	}
	if ((upload2 == upload3 || upload4 || upload5) && (!duplicates) && (upload1 != ""))
	{
		missinginfo += "\n     -  Duplicate Attachments Selected";
		duplicates++;
	}......

but this gets old and long in a hurry.

i need some sort of loop that loops through 'upload' element(?) 1-5 and compare the values (if it's not blank).

thanks.

 

[tsuji]

You can do it like this.
[tt]
function checkdupfile(obj) { //obj: a form element
var celem=obj.elements;
var cfile=new Array();
var cfname=new Array();
for (var i=0;i<celem.length;i++) {
if (celem.type=="file") {
if (celem.value.replace(/\s/g,"").length!=0) {
cfile.push (celem);
cfname.push (escape(celem.value));
}
}
}

alert("Number of files you have chosen to upload : " + cfile.length);
//or do something if the number is lower than some number

var sbase=cfname.join(" ");
var bdup=false;
for (var i=cfile.length-1;i>-1;i--) {
var rx=new RegExp("\\b"+cfname+"\\b","gi");
var cm=sbase.match(rx);
if (cm && cm.length>1) {
cfile.focus();
bdup=true;
break;
}
}
if (bdup) {
alert("duplicated filess are found");
//or do something
} else {
alert("no duplicated file is found");
//or do something
}
}
[/tt]

 

[ibjdt]

thanks for the help, but i cannot get the script to work,
have you tried it??

in the form tag i have


onSubmit="checkdupfile();"


is this correct??

thanks.

 

[tsuji]

>in the form tag i have
>onSubmit="checkdupfile();"

If it is in the form tag, it is this.

[tt]onsubmit="return checkdupfile(this)"[/tt]

_and_ you add some "return false" provision inside the function. Under what condition depends on your concrete needs. I cannot say for the minimum number because I don't know the number, but I can say for the existing of duplicate file. Like this. If I assume the minimum number be one (1), then change the variable setting.
[tt]
function checkdupfile(obj) { //obj: a form element
[green]var minnum=1;[/green] //change to your need
var celem=obj.elements;
var cfile=new Array();
var cfname=new Array();
for (var i=0;i<celem.length;i++) {
if (celem.type=="file") {
if (celem.value.replace(/\s/g,"").length!=0) {
cfile.push (celem);
cfname.push (escape(celem.value));
}
}
}

alert("Number of files you have chosen to upload : " + cfile.length);
//or do something if the number is lower than some number
[blue]if (cfile.length<minnum) {
return false;
}[/blue]

var sbase=cfname.join(" ");
var bdup=false;
for (var i=cfile.length-1;i>-1;i--) {
var rx=new RegExp("\\b"+cfname+"\\b","gi");
var cm=sbase.match(rx);
if (cm && cm.length>1) {
cfile.focus();
bdup=true;
break;
}
}
if (bdup) {
alert("duplicated files are found");
//or do something
[blue]return false;[/blue]
} else {
alert("no duplicated file is found");
//or do something
[blue]return true;[/blue]
}
}
[/tt]

 

[ibjdt]

thanks.

works perfectly!!