String Processing using ABAP string template

String Processing is one of the core components of any development. More so true when you are working with ABAP. String processing can be painful sometimes especially when you are merging or trying to embed one or more variables.

In this post, I wanted to share the usage of String templates to help process strings effortlessly.
But first,

What is a string template?

Simply Put, A string template is enclosed in two "|" (Pipe symbol) characters.

 Example:   

	DATA:
	lv_string TYPE string,
	lv_string_template TYPE string.
	lv_string = `This is a string created using string literals`.
	lv_string_template = |This is a string created using string templates|.

view raw str_tmplt_simple_Ex.abap hosted with ❤ by GitHub

But there is more, string templates are a powerful tool that does more than just replace string literal.

One of the biggest benefits of String templates is the elimination of helper variables.
A string template has three components:

Literal Text:

Represents its exact character string. meaning what you see is what you get.
Ex:

lv_String = | This is a literal text|.

view raw str_tmplt_literal_ex.abap hosted with ❤ by GitHub

Embedded Expressions:

An embedded expression is defined inside an opening and a closing curly bracket { ... } within string templates and can hold:

Data objects like variables/constants,

	report syst-repid.
	DATA:
	lv_String TYPE string.
	START-OF-SELECTION.
	lv_String = |The logged on user is: { syst-uname }|.
	cl_demo_text=>show_string( lv_String ).

view raw str_tmplt_embed_expr_var_ex.abap hosted with ❤ by GitHub

  

Calculation expressions like: 1 + 1,

	report syst-repid.
	DATA:
	lv_String TYPE string.
	START-OF-SELECTION.
	lv_String = |5 multiplied by 5 is : { 5 * 5 }|.
	cl_demo_text=>show_string( lv_String ).

view raw str_tmplt_embed_expr_calc_exp_ex.abap hosted with ❤ by GitHub

Predefined functions like LINES/TO_UPPER/STRLEN,

	report syst-repid.
	DATA:
	lv_String TYPE string.
	START-OF-SELECTION.
	lv_String = | lowercase to { to_upper( |uppercase| ) } |.
	cl_demo_text=>show_string( lv_String ).

view raw str_tmplt_embed_expr_predif_func_ex.abap hosted with ❤ by GitHub

Functional methods( methods having only one returning parameter),

	report syst-repid.
	DATA:
	lv_String TYPE string.
	CLASS lcl_main DEFINITION.
	PUBLIC SECTION.
	CLASS-METHODS:
	ret_String RETURNING VALUE(rv_string) TYPE string.
	ENDCLASS.
	CLASS lcl_main IMPLEMENTATION.
	METHOD ret_String .
	rv_string = |The string was returned from a functional method.|.
	ENDMETHOD.
	ENDCLASS.
	START-OF-SELECTION.
	lv_String = | class methods says: { lcl_main=>ret_String( ) } |.
	cl_demo_text=>show_string( lv_String ).

view raw str_tmplt_embed_expr_func_meth_ex.abap hosted with ❤ by GitHub

Method chaining: Notice how ret_string is passed to to_upper using method chaining.

	report syst-repid.
	DATA:
	lv_String TYPE string.
	CLASS lcl_main DEFINITION.
	PUBLIC SECTION.
	CLASS-METHODS:
	ret_String RETURNING VALUE(rv_string) TYPE string.
	ENDCLASS.
	CLASS lcl_main IMPLEMENTATION.
	METHOD ret_String .
	rv_string = |The string was returned from a functional method.|.
	ENDMETHOD.
	ENDCLASS.
	START-OF-SELECTION.
	lv_String = | class methods says: { to_upper( lcl_main=>ret_String( ) ) } |.
	cl_demo_text=>show_string( lv_String ).

view raw str_tmplt_embed_expr_meth_chain_ex.abap hosted with ❤ by GitHub

That's not it,

These embedded expressions can be formatted using formatting options like DATE, TIME, PAD, CASE, and many more.

Control Characters: 

String templates interpret the character combinations \n, \r, and \t as control characters.
\n represents Line break,
\r represents a return,
\t represents tabulator or tab.

An Example:

	report syst-repid.
	DATA:
	lv_String TYPE string.
	START-OF-SELECTION.
	lv_String = |Normal first line.\r\tonetab\tsecondtab\tthirdtab \nLast line.|.
	cl_demo_text=>show_string( lv_String ).

view raw str_tmplt_embed_expr_control_char_ex.abap hosted with ❤ by GitHub

All of the control characters can be displayed by using the escape character "\" if needed.

As you can see, String templates are a very powerful yet simple tool. Hope your day-to-day life becomes easier using them.

FOr more examples and code snippets,Check out the ABAP string templates examples