ABAP Multiline Strings: Create, Manipulate, and Display

In SAP ABAP, you can work with multiline strings by using special characters such as newlines (CR/LF) or leveraging ABAP’s string handling capabilities. Here are some methods to create, manipulate, and display multiline strings in ABAP.

1. Using `&&` (Concatenation) with `CL_ABAP_CHAR_UTILITIES=>CR_LF` for Multiline Strings

You can concatenate strings with newline characters (CR/LF) to create multiline strings.

DATA: lv_string TYPE string.

lv_string = 'Hello ABAP' && cl_abap_char_utilities=>cr_lf && 'This is a multiline string.'.

WRITE: / lv_string.

Explanation: The && operator is used for concatenation, and cl_abap_char_utilities=>cr_lf adds a newline (\r\n) between the lines.

2. Using `DATA` Statements with `TEXT` Option (ABAP 7.40 and Later)

Starting from ABAP 7.40, you can directly define multiline strings using the DATA statement with the TEXT option.

DATA(lv_string) = `Hello ABAP
This is a multiline string in ABAP
using the TEXT option.`.

WRITE: / lv_string.

Explanation: This approach allows you to define a multiline string directly within the DATA statement.

3. Using `CONCATENATE` for Multiline String Construction

If you need to build a multiline string from different parts of code, you can use the CONCATENATE statement.

DATA: lv_string TYPE string.

CONCATENATE 'Hello ABAP' cl_abap_char_utilities=>cr_lf
            'This is a multiline string' cl_abap_char_utilities=>cr_lf
            'with CONCATENATE' INTO lv_string SEPARATED BY space.

WRITE: / lv_string.

Explanation: The CONCATENATE statement can be used to add multiple lines to a string. Each line is separated by a newline character.

4. Using `LOOP` for Multiline String Construction

You can also build a multiline string from a table of strings by looping through the table and concatenating them.

DATA: lt_lines TYPE TABLE OF string,
      lv_string TYPE string.

APPEND 'Hello ABAP' TO lt_lines.
APPEND 'This is a multiline string.' TO lt_lines.
APPEND 'Generated using a loop.' TO lt_lines.

LOOP AT lt_lines INTO DATA(lv_line).
  CONCATENATE lv_string lv_line INTO lv_string SEPARATED BY cl_abap_char_utilities=>cr_lf.
ENDLOOP.

WRITE: / lv_string.

Explanation: The loop constructs the multiline string by iterating over the lines in the internal table lt_lines and concatenating them.

5. Handling Multiline Strings in Output

When you print a multiline string (e.g., in reports), the newlines (CR/LF) will be respected and displayed properly in the output.

DATA: lv_string TYPE string.

lv_string = 'Hello ABAP' && cl_abap_char_utilities=>cr_lf &&
            'This is a multiline string' && cl_abap_char_utilities=>cr_lf &&
            'displayed correctly.'.

WRITE: / lv_string.

Explanation: This method combines the && operator with cl_abap_char_utilities=>cr_lf to manage multiline strings and display them as separate lines in the output.

Best Practices for Multiline Strings

Method	Best For	Version
Concatenating with `CR_LF`	Creating multiline strings from individual lines	All ABAP versions
Using `TEXT` option (ABAP 7.40+)	Defining a multiline string directly	ABAP 7.40 and above
`CONCATENATE` statement	Concatenating multiple strings with specific delimiters	All ABAP versions
Using `LOOP` with internal table	Dynamically creating a multiline string from internal tables	All ABAP versions

Display Considerations

When displaying multiline strings in ABAP reports or UI elements, ensure the format respects line breaks (for example, if you’re working with HTML or XML, use appropriate tags or encoding).

1. Using && (Concatenation) with CL_ABAP_CHAR_UTILITIES=>CR_LF for Multiline Strings

2. Using DATA Statements with TEXT Option (ABAP 7.40 and Later)

3. Using CONCATENATE for Multiline String Construction