Entry

How can I index form elements with a name like "field-name"?

Feb 14th, 2001 13:06
Paulo Eduardo Neves, Jeff Pfaff,

Usually if you have a form like this:

  <FORM NAME="formName">
  <INPUT NAME="fieldName" ...>
  <INPUT NAME="anotherFieldName" ...>

you can reference the form elements using: 

document.formName.fieldName
document.formName.anotherFieldName

However you may have a form with field names containing characters 
which are not allowed in identifiers in JavaScript, such as:

  <INPUT NAME="anotherField-Name" ...>

Using  'document.formName.anotherField-Name' to reference this element 
will cause an error because javascript will view it as a minus sign. 


An easy work around for this is to reference the elements this way 
instead:

document.formName.elements[x]

where x is the number of each 'input' statement in your form.

using this method, you can safely reference the following form 
variables: 

  <FORM NAME="formName">
  <INPUT NAME="field-Name" ...>
  <INPUT NAME="anotherField-Name" ...>
  </FORM>

With these statements

document.formName.elements[0]       (for field-Name)
document.formName.elements[1]       (for anotherField-Name)

Notice that the numbering starts with zero!

You can also access the array notation, it will probably make your code
clearer:
document.formName['anotherField-Name']