JavaScript Form List Key to Index

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JavaScript references list menu (dropdown) elements by their index number, not by the list menu’s key. So if you want to preselect a list menu using JavaScript and you know they key in the key/value pairs that comprise the listmenu, here is a simple function I wrote which you pass the field id and the key you want the index for.

[js]
function key2index(field,value){
for (i=0; i<$(field).options.length; i++){
if ($(field).options[i].value == value) return i;
} return 0;
}
[/js]