Referencing R/3 Fields (SAP Library - HTMLBusiness Language Reference)

Referencing R/3 Fields

The main task of HTML^Business is to tell the Internet Transaction Server (ITS) how to transfer data between R/3 screens and the HTML templates.

At runtime, there are two types of R/3 field known to the ITS:

Fields passed from an R/3 screen

Only screen fields are visible to the ITS. Fields known only to the module pool are not visible.

Fields passed via the RFC channel

These are fields transferred by the ABAP program using the ITS macros FIELD_SET or FIELD_TRANSPORT.

Referencing Screen Fields

Field replacement is the simplest form of HTML^Business statement. This controls how screen values are copied to the HTML page and how values from the Web browser are integrated into entry fields on the R/3 screen.

There is normally a 1:1 relationship between screen fields and HTML fields, whether you are reading from or writing to the screen. However, large text areas are an exception to this rule.

With the exception of reserved keywords, every HTML^Business expression is treated as a screen field name:

If the ITS finds a match for a field name, it copies the R/3 field contents to the HTML page
If the ITS finds no match for a field name, it replaces the variable with an empty string

To display R/3 screen field data in your HTML page, you simply enclose the R/3 field name in <server>...</server> tags or back quotes.

Field Identifier Syntax

The following table shows the syntax for referencing R/3 screen fields in HTML^Business. The attributes provide additional information about the field.

Name	Syntax
Field	{ ^ } identifier [ [ expression ] ] [. attribute ]
Attribute	dim \|
	disabled \|
	exists \|
	label \|
	maxSize \|
	name \|
	type \|
	value \|
	visSize

In HTML^Business, field identifiers should conform to the same conventions as in other programming languages such as C or JavaScript.

These conventions are summarized in the following table:

Field Identifier Component	Possible Characters	Values
First character	Letters	a…z, A…Z
	Underscore	_
	Tilde	~
Subequent characters	Letters	a…z, A…Z
	Underscore	_
	Tilde	~
	Digits	0…9
	Hyphen	-

Example

The following are valid field identifiers:

nCustomers
_foo_bar
~frame
date1
ordered_items
vbcom-kunde

You must enclose the entire field identifier in single quotation marks:

If you use other characters.
If you use the same name as a keyword.

Example

'*vbcom-kunde'
'$@#identifier()***'
'from'

Identifiers such as vbcom-kunde do not need single quotes, because the hyphen is legal. Simply write `vbcom-kunde` instead of `'vbcom-kunde'` .

However, if you want to use arithmetic expressions that contain minus signs, there must be at least one space before and after the minus sign:

Limiting the Number of Characters

You can limit the number of characters per field that are transferred from the HTML page to the screen by entering a colon after the field name and then specifying the number of characters. You must specify the length between the field name and the index.

If you limit the number of characters in this way, extra characters are lost. This does not apply when the field is an array and you have not specified an explicit index with [] . In this case, characters beyond your specified limit are included in a new line of the step loop. This is necessary when processing large text areas.

Field Attributes

There are several attributes you can use to find out properties of R/3 fields. For further information, see Getting R/3 Field Attributes.

Name	Syntax
Field	{ ^ } identifier [ [ expression ] ] [. attribute ]
Attribute	dim \|
	disabled \|
	exists \|
	label \|
	maxSize \|
	name \|
	type \|
	value \|
	visSize