9 APEX_JAVASCRIPT

The APEX_JAVASCRIPT package provides utility functions for adding dynamic JavaScript code to HTTP output. This package is usually used for plug-in development.

Topics:

ADD_ATTRIBUTE Function Signature 1

This function returns the attribute and the attribute's escaped text surrounded by double quotes.

Note:

This function does not escape HTML tags. It only prevents HTML tags from breaking the JavaScript object attribute assignment. To prevent XSS (cross site scripting) attacks, you must also call SYS.HTF.ESCAPE_SC to prevent embedded JavaScript code from being executed when you inject the string into the HTML page.

Syntax

APEX_JAVASCRIPT.ADD_ATTRIBUTE (
    p_name       IN VARCHAR2,
    p_value      IN VARCHAR2,
    p_omit_null  IN BOOLEAN:=TRUE,
    p_add_comma  IN BOOLEAN:=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-1 describes the parameters available in the ADD_ATTRIBUTE function signature 1.

Table 9-1 ADD_ATTRIBUTE Signature 1 Parameters

Parameter Description

p_name

Name of the JavaScript object attribute.

p_value

Text to be assigned to the JavaScript object attribute.

p_omit_null

If set to TRUE and p_value is empty, returns NULL.

p_add_comma

If set to TRUE, a trailing comma is added when a value is returned.

Example

Adds a call to the addEmployee JavaScript function and passes in a JavaScript object with different attribute values. The output of this call will look like:

addEmployee(
  {"FirstName":"John",
   "LastName":"Doe",
   "Salary":2531.29,
   "Birthday":new Date(1970,1,15,0,0,0),
   "isSalesman":true
  });

As the last attribute you should use the parameter combination FALSE (p_omit_null), FALSE (p_add_comma) so that the last attribute is always generated. This avoids that you have to check for the other parameters if a trailing comma should be added or not.

apex_javascript.add_onload_code (
    'addEmployee('||
        '{'||
        apex_javascript.add_attribute('FirstName',  sys.htf.escape_sc(l_first_name))||
        apex_javascript.add_attribute('LastName',   sys.htf.escape_sc(l_last_name))||
        apex_javascript.add_attribute('Salary',     l_salary)||
        apex_javascript.add_attribute('Birthday',   l_birthday)||
        apex_javascript.add_attribute('isSalesman', l_is_salesman, false, false)||
        '});' );

ADD_ATTRIBUTE Function Signature 2

This function returns the attribute and the attribute's number.

Syntax

APEX_JAVASCRIPT.ADD_ATTRIBUTE (
    p_name       IN VARCHAR2,
    p_value      IN NUMBER,
    p_omit_null  IN BOOLEAN:=TRUE,
    p_add_comma  IN BOOLEAN:=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-2 describes the parameters available in the ADD_ATTRIBUTE function signature 2.

Table 9-2 ADD_ATTRIBUTE Signature 2 Parameters

Parameter Description

p_name

Name of the JavaScript object attribute.

p_value

Number which should be assigned to the JavaScript object attribute.

p_omit_null

If set to TRUE and p_value is empty, returns NULL.

p_add_comma

If set to TRUE, a trailing comma is added when a value is returned.

Example

See example for ADD_ATTRIBUTE Function Signature 1.

ADD_ATTRIBUTE Function Signature 3

This function returns the attribute and a JavaScript boolean of true, false, or null.

Syntax

APEX_JAVASCRIPT.ADD_ATTRIBUTE (
    p_name       IN VARCHAR2,
    p_value      IN BOLLEAN,
    p_omit_null  IN BOOLEAN:=TRUE,
    p_add_comma  IN BOOLEAN:=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-3 describes the parameters available in the ADD_ATTRIBUTE function signature 3.

Table 9-3 ADD_ATTRIBUTE Signature 3 Parameters

Parameter Description

p_name

Name of the JavaScript object attribute.

p_value

Boolean assigned to the JavaScript object attribute.

p_omit_null

If p_omit_null is TRUE and p_value is NULL the function returns NULL.

p_add_comma

If set to TRUE a trailing comma is added when a value is returned.

Example

See example for ADD_ATTRIBUTE Function Signature 1

ADD_ATTRIBUTE Function Signature 4

This function returns the attribute and the attribute's date. If p_value is null the value null is returned.

Syntax

APEX_JAVASCRIPT.ADD_ATTRIBUTE (
    p_name       IN VARCHAR2,
    p_value      IN DATE,
    p_omit_null  IN BOOLEAN:=TRUE,
    p_add_comma  IN BOOLEAN:=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-4 describes the parameters available in the ADD_ATTRIBUTE function signature 4.

Table 9-4 ADD_ATTRIBUTE SIgnature 4 Parameters

Parameter Description

p_name

Name of the JavaScript object attribute.

p_value

Date assigned to the JavaScript object attribute.

p_omit_null

If p_omit_null is TRUE and p_value is NULL the function returns NULL.

p_add_comma

If set to TRUE a trailing comma is added when a value is returned.

Example

See example for ADD_ATTRIBUTE Function Signature 1

ADD_INLINE_CODE Procedure

This procedure adds a code snippet that is included inline into the HTML output. For example, you can use this procedure to add new functions or global variable declarations. If you want to execute code you should use ADD_ONLOAD_CODE Procedure.

Syntax

APEX_JAVASCRIPT.ADD_INLINE_CODE (
    p_code       IN VARCHAR2,
    p_key        IN VARCHAR2 DEFAULT NULL);

Parameters

Table 9-5 describes the parameters available in the ADD_INLINE_CODE procedure.

Table 9-5 ADD_INLINE_CODE Parameters

Parameter Description

p_code

JavaScript code snippet. For example: $s('P1_TEST',123);

p_key

Identifier for the code snippet. If specified and a code snippet with the same name has already been added the new code snippet will be ignored. If p_key is NULL the snippet will always be added.

Example

The following example includes the JavaScript function initMySuperWidget in the HTML output. If the plug-in is used multiple times on the page and the add_inline_code is called multiple times, it is added once to the HTML output because all calls have the same value for p_key.

apex_javascript.add_inline_code (
    p_code => 'function initMySuperWidget(){'||chr(10)||
              '  // do something'||chr(10)||
              '};',
    p_key  => 'my_super_widget_function' );

ADD_LIBRARY Procedure

This procedure adds the script tag to load a JavaScript library. If a library has been added it will not be added a second time.

Syntax

APEX_JAVASCRIPT.ADD_LIBRARY (
    p_name           IN VARCHAR2,
    p_directory      IN VARCHAR2 DEFAULT wwv_flow.g_image_prefix||'javascript/',
    p_version        IN VARCHAR2 DEFAULT c_apex_version,
    p_skip_extension IN BOOLEAN DEFAULT FALSE);

Parameters

Table 9-6 describes the parameters available in the ADD_LIBRARY procedure.

Table 9-6 ADD_LIBRARY Parameters

Parameter Description

p_name

Name of the JavaScript file. Must not use .js when specifying.

p_directory

Must have a trailing slash.

p_version

Version identifier. It is recommended, but is optional, to add this to the library name.

p_skip_extension

If TRUE the extension .js is NOT added.

Example

The following example includes the JavaScript library file my_library.1.2.min.js in the directory specified by p_plugin.file_prefix. This is the recommended syntax when you include your own JavaScript files in a plug-in.

apex_javascript.add_library (
    p_name      => 'mylibrary.1.2.min'
    p_directory => p_plugin.file_prefix,
    p_version   => null );

ADD_ONLOAD_CODE Procedure

This procedure adds a javascript code snippet to the HTML output which is executed by the onload event. If an entry with the same key exists it will be ignored. If p_key is NULL the snippet will always be added.

Syntax

APEX_JAVASCRIPT.ADD_ONLOAD_CODE (
    p_code           IN VARCHAR2,
    p_key            IN VARCHAR2 DEFAULT NULL);

Parameters

Table 9-7 describes the parameters available in the ADD_ONLOAD_CODE procedure.

Table 9-7 ADD_ONLOAD_CODE Parameters

Parameter Description

p_code

Javascript code snippet to be executed during the onload event.

p_key

Any name to identify the specified code snippet. If specified, the code snippet is added if there has been no other call with the same p_key. If p_key is NULL the code snippet is always added.

Example

Adds the JavaScript call initMySuperWidget()to the onload buffer. If the plug-in is used multiple times on the page and the add_onload_code is called multiple times, it is added once to the HTML output because all calls have the same value for p_key

apex_javascript.add_onload_code (
    p_code => 'initMySuperWidget();'
    p_key  => 'my_super_widget' );

ADD_VALUE Function Signature 1

This function returns the escaped text surrounded by double quotes. For example, this string could be returned "That\'s a test".

Note:

This function does not escape HTML tags. It only prevents HTML tags from breaking the JavaScript object attribute assignment. To prevent XSS (cross site scripting) attacks, you must also call SYS.HTF.ESCAPE_SC to prevent embedded JavaScript code from being executed when you inject the string into the HTML page.

Syntax

APEX_JAVASCRIPT.ADD_VALUE (
    p_value          IN VARCHAR2,
    p_add_comma      IN BOOLEAN :=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-8 describes the parameters available in the ADD_VALUE signature 1 function.

Table 9-8 ADD_VALUE Signature 1 Parameters

Parameter Description

p_value

Text to be escaped and wrapped by double quotes.

p_add_comma

If p_add_comma is TRUE a trailing comma is added.

Example

This example adds some JavaScript code to the onload buffer. The value of p_item.attribute_01 is first escaped with htf.escape_sc to prevent XSS attacks and then assigned to the JavaScript variable lTest by calling apex_javascript.add_value. Add_value takes care of properly escaping the value and wrapping it into double quotes. Because commas are not wanted, p_add_comma is set to FALSE.

apex_javascript.add_onload_code (
    'var lTest = '||apex_javascript.add_value(sys.htf.escape_sc(p_item.attribute_01), FALSE)||';'||chr(10)||
    'showMessage(lTest);' );

ADD_VALUE Function Signature 2

This function returns p_value as JavaScript number, if p_value is NULL the value null is returned.

Syntax

APEX_JAVASCRIPT.ADD_VALUE (
    p_value          IN NUMBER,
    p_add_comma      IN BOOLEAN :=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-8 describes the parameters available in the ADD_VALUE signature 2 function.

Table 9-9 ADD_VALUE Signature 2 Parameters

Parameter Description

p_value

Number which should be returned as JavaScript number.

p_add_comma

If p_add_comma is TRUE a trailing comma is added. Default is TRUE.

Example

See example for ADD_VALUE Function Signature 1 .

ADD_VALUE Function Signature 3

This function returns p_value as JavaScript boolean. If p_value is NULL the value null is returned.

Syntax

APEX_JAVASCRIPT.ADD_VALUE (
    p_value          IN BOOLEAN,
    p_add_comma      IN BOOLEAN :=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-10 describes the parameters available in the ADD_VALUE signature 3 function.

Table 9-10 ADD_VALUE Signature 3 Parameters

Parameter Description

p_value

Boolean which should be returned as JavaScript boolean.

p_add_comma

If p_add_comma is TRUE a trailing comma is added. Default is TRUE.

Example

See example for ADD_VALUE Function Signature 1 .

ADD_VALUE Function Signature 4

This function returns p_value as JavaScript date object, if p_value is NULL the value null is returned.

Syntax

APEX_JAVASCRIPT.ADD_VALUE (
    p_value          IN NUMBER,
    p_add_comma      IN BOOLEAN :=TRUE)
RETURN VARCHAR2;

Parameters

Table 9-11 describes the parameters available in the ADD_VALUE signature 4 function.

Table 9-11 ADD_VALUE Signature 4 Parameters

Parameter Description

p_value

Date which should be returned as JavaScript date object.

p_add_comma

If p_add_comma is TRUE a trailing comma is added. Default is TRUE.

Example

See example for ADD_VALUE Function Signature 1 .

Escape Function

This function escapes a text to be used in JavaScript. This function makes the following replacements:

Table 9-12 Table of Replacement Values

Replacement After replacement

\

\\

/

\/

"

\u0022

'

\u0027

tab

\t

chr(10)

\n

Note:

This function does not escape HTML tags. It only prevents HTML tags from breaking the JavaScript object attribute assignment. To prevent XSS (cross site scripting) attacks, you must also call SYS.HTF.ESCAPE_SC to prevent embedded JavaScript code from being executed when you inject the string into the HTML page.

Syntax

APEX_JAVASCRIPT.ESCAPE (
    p_text  IN VARCHAR2)
RETURN VARCHAR2;

Parameters

Table 9-13 describes the parameters available in the ESCAPE function.

Table 9-13 ESCAPE Parameters

Parameter Description

p_text

Text to be escaped.

Example

Adds some JavaScript code to the onload buffer. The value of p_item.attribute_01 is first escaped with htf.escape_sc to prevent XSS attacks and then escaped with apex_javascript.escape to prevent that special characters like a quote break the JavaScript code.

apex_javascript.add_onload_code (
    'var lTest = "'||apex_javascript.escape(sys.htf.escape_sc(p_item.attribute_01))||'";'||chr(10)||
    'showMessage(lTest);' );