Advanced Arrays

Initialize all global variables. This allows any function to access, their last known values. elim, LookFor, & LookBy are string variables. k, g, & n are numbers.

The array FoundArray is also initialized, it will be used to build an array of search results, on the fly.

function listing(first,last,dept,phone,ext,email) {
this.first = first;
this.last = last;
this.dept = dept;
this.phone = phone;
this.ext = ext;
this.email = email; }

The function listing, sets up the columnar headings of the 2D array directory which follows.

The properties first,last,dept,phone,ext,email, correspond to a similarly named text object.

directory = new Array(6)

directory[0] = new listing
("bob","johnson","accounting","(206)
555-5555","3704","jbob@company.com")

directory[1] = new listing
("carrol","ethridge","operations","(206)
555-5555","3712","carrole@company.com")

directory[2] = new listing
("bob","allen","accounting","(206)
555-5505","6304","bob@company.com")

directory[3] = new listing
("henry","murphy","sales","(621)
555-5855","9004","murph@company.com")

directory[4] = new listing
("susan","jones","shipping","(621)
555-5855","6774","jones@company.com")

directory[5] = new listing
("susan","murphy","accounting","(621)
555-5855","6774","murphy@company.com")

The array directory contains six entries [0]-[6]. Each listing contains the the six properties first,last,dept,phone,ext,email.

The script will search each listing by the property that corresponds to the users search input. For example, if the user inputs Sales into the form dept field, the script will search the listing property dept.

All of the listing properties are entered as lowercase strings. This is to eliminate the need for case conversion of the listing.property, when the search is performed.

Instead, the LookFor string used later in the script is converted toLowerCase(), to match the convention used in the array.

LookNow searches the forms fields using the document object's forms elements array. forms[0].elements[j]. If the field is "" || null, the element is skipped using continue;.

If a value is found, the script assigns that value to LookFor, notes the field that it came from as LookBy, sends them both to SearchNow, & finally, break's the loop.

Some of the global variables are reset here, to enable a fresh search. To keep the results of the last search available, n & k would be left out here and added to an onReset="n=0;k=0" event handler to the form tag.

N
O
T
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The for loop in LookNow, searches the
(document.forms[0].elements.length) - 4. The - 4 is to prevent the function from attempting to search the form button, submit and reset objects.

SearchNow(LookFor,LookBy) {
i = 0
for ( var i = 0 ; i < directory.length ; i++ ) {

if ( LookFor != eval("directory[" + i + "]." + LookBy ))
{ continue; }

{k++; OutPutPrep(i,k); }
alert("Your search for " + elim + ",\nyielded " + k + " matches") }

SearchNow takes the values passed to it by LookNow: LookFor & LookBy and uses them to compare the appropriate listing property in the directory array.

If a match is found, i records the row it was found in, increments k++ and sends them both to OutPutPrep, then continues searching for additional matches.

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The eval() string method is used to convert the string "directory[" + i + "]." + LookBy to an actual object. This is done because LookBy is a string. For example, eval() may return directory[i].first or directory[i].ext, etc.

function OutPutPrep(i,k) {
n = 0

for ( n ; n < k ; n++ ) {

FoundArray[n] = "directory[" + i + "]"; OutPutResult(0); continue;}

OutPutPrep populates the array FoundArray, that was declared earlier. FoundArray uses k to determine its length.

Since each i passed to OutPutPrep, also has a paired k++, k keeps track of how many i's have passed through OutPutPrep's gate. n increments for each i,k pair, generating FoundArray's rows on the fly.

function update(g) { return 1; }

update(g) keeps track of which row in the FoundArray array is being viewed.

function NextName() {
update(g++);

if ( g > k-1 ) { g = k-k; } OutPutResult(g);}

NextName(), first reports it's destination to update(g). The internal reset if ( g > k-1 ), ensures that g does not step beyond the relative bounds of FoundArray.

function PrevName() {
update(g--);

if ( g < 0 ) { g = k-1; } OutPutResult(g);}

PrevName(), first reports it's destination to update(g). The internal reset if ( g < 0 ), ensures that g does not step beyond the relative bounds of FoundArray.

function OutPutResult() {

if ( k != 0 ) {

document.forms[0].elements[0].value = eval (FoundArray[g] + ".first");

document.forms[0].elements[1].value = eval (FoundArray[g] + ".last");

document.forms[0].elements[2].value = eval (FoundArray[g] + ".dept");

document.forms[0].elements[3].value = eval (FoundArray[g] + ".phone");

document.forms[0].elements[4].value = eval (FoundArray[g] + ".ext");

document.forms[0].elements[5].value = eval (FoundArray[g] + ".email"); }}}

//-->
</script>

OutPutResult first checks to make sure that FoundArray is not empty by testing if ( k != 0 ).This prevents eager users from tripping an error by clicking on the navigation buttons Prev & Next before searching the array.

simply writes the search results to the form.