Constructor
new CspExpressionEvaluator(options)
Parameters:
| Name | Type | Description | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
options |
Object |
Properties
|
Final Class: CspExpressionEvaluator
Oracle® JavaScript Extension Toolkit (JET)
8.0.0
F18189-01
CspExpressionEvaluator
- Version:
- 8.0.0
- Since:
- 7.1.0
- Module:
- ojcspexpressionevaluator
Module usage
See JET Module Loading for an overview of module usage within JET.
Javascript Import Format
define(['ojs/ojcspexpressionevaluator'], function(CspExpressionEvaluator) { // Application should call API on CspExpressionEvaluator })
Typescript Import Format
//This class is exported directly as module. To import it
import CspExpressionEvaluator= require("ojs/ojcspexpressionevaluator");
JET In Typescript
A detailed description of working with JET elements and classes in your typescript project can be found at: JET Typescript Usage.
Final classes in JET
Classes in JET are generally final and do not support subclassing. At the moment, final is not enforced. However, this will likely change in an upcoming JET release.
Description
A class for creating CSP-compliant evaluators of JavaScript expressions
The default JET expression evaluator cannot be used when Content Security Policy prohibits unsafe evaluations. In order to replace the default evaluator with the JET CSP-compliant evaluator, create and pass an instance of CspExpressionEvaluator class to the Config.setExpressionEvaluator() method. This method must be called before applying knockout bindings in the application for the first time.
Any extra context required for evaluating expressions can be passed to the object constructor using globalScope property.
Config.setExpressionEvaluator(new CspExpressionEvaluator());
Expressions supported by the JET CspExpressionEvaluator
- Identifiers, e.g.
[[value]]. - Members, e.g.
[[router.stateId]]. - Literals, e.g.
[['abc']]. - Function callbacks, e.g.
[[getColor('customer', id)]]. - Unary operators are limited to '-', '+', '~', '!', e.g.
[[-100]]. - Binary operators, e.g.
[[value + '.png']]. - Logical operators, e.g.
[[a && b]]or[[a || b]]. - Conditional or ternary operators, e.g.
[[test ? consequent : alternate]]. - Array literals, e.g.
[a, b, c]. - Object literals, e.g.
[[{'selection_state': selected}]]. - Functions are limited to a single statement, e.g.
[[function(){return 'abc'}]]. - 'new' operator such as
'new Object()'
Expression limitations:
The following code is not supported in expressions:
- JavaScript operations such as
'var a=b;' - Blocks of code such as
'if (...){}' - Increment/decrement operators such as
'x++'or'x--' - Assignment operators such as
'='