New to Javascript

[billswann]

Hello,

I am new to javascript but have a problem that I haven;t been able to find an answer for. I have the line in a script that was written by someone else that is no longer avaiable. That line is frm.attachEvent("onsubmit", extrapolate); I would like that line to be condition only on a signle button instead of any button being clicked.

Thank you in advance for any suggestions. :confused:

[toicontien]

We need to see the full HTML and JavaScript for the page. The line of javascript you gave us is very ambiguous.

[billswann]

This is the javascript

//==================================================================================================
// CRTTEXTAREA: concatenate a textarea from multiple 25 char fields
// parent: container element in which to place the textarea
// frm: form containing fields for textarea
// fields: array of field names
//==================================================================================================

function crtTextArea(parent, frm, fields) {

// Begin constructing text string from fields
var textout = "";
var trimtextout = ""; // stores version trimmed of trailing line feeds
var lastLineExtraSpace; // count of extra space on last line

for (var n in fields) {
if (frm[fields[n]]) {

// Add contents of field values to string
var txt = frm[fields[n]].value;

// If first word of new text wouldn't fit on the previous line,
// assume text is meant to wrap
var words = txt.split(' ');
if (n == 0) {

// First line; neither space nor newline

} else if (words && words[0] && words[0].length > lastLineExtraSpace) {

// No line feed; text should wrap
txt = " " + txt;
} else {

// Otherwise insert line feed before new text
txt = "\n" + txt;
}

textout += txt;
if (txt != "")
trimtextout = textout;

lastLineExtraSpace = 25 - txt.length - 2;
} else {

// Break out of loop when no more fields found
fields.length = n;
break;
}
}

// Create text area to fit correct number of fields
largeFld = document.createElement("textarea");
largeFld.rows = n;
largeFld.cols = 25;
largeFld.innerText = trimtextout;
parent.appendChild(largeFld);

//==================================================================================
// Put TEXTAREA back into separate 25 char fields when specified buttons are clicked
//===================================================================================

var extrapolate = function(){

// Create pattern object and result array and counter
pattern = /([^ ]{1,25} ?)/g;
var b = new Array("");
var j = 0;

// First break field value into lines

var lines = largeFld.value.split('\n');
for (var lnum in lines) {
var line = lines[lnum];

b[j] = "";

// Match each line against the pattern, which breaks
// the line into words of at most 25 chars
a = line.match(pattern);
if (a) {
for (i=0; i<a.length; i++) {

// If word will not fit on line, place
// word on next line
if(b[j].length + a[i].length > 25) {
j++;
b[j] = "";
}

// Add word to line
b[j] = b[j] + a[i];
}

// Advance to next line
j++;
}
}

// Blank remaining line fields
for (;j<fields.length;j++) {
b[j] = "";
}

// Assign items in array b to form fields
j = 0;
for (var n in fields) {
frm[fields[n]].value = b[j];
j++;
}
}
//==============================
// END EXTRAPOLATE
//==============================

// Attach extrapolate function to fire when form is submitted
frm.attachEvent("onsubmit", extrapolate);

}

//==============================
// END CRTTEXTAREA
//==============================

[billswann]

Added HTML in attachment in preivous reply.

[theRatWonder]

As it's an "onsubmit" handler it can only apply to the whole form.

If you want it just for one button it would have to be an "onclick" handler:

document.getElementById(<buttonId>).attachEvent('onclick',extrapolate);