pip-services3-commons-node
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Portable abstractions and patterns for Pip.Services in Node.js
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TypeScript
/**
* Helper class to perform property introspection and dynamic reading.
*
* In contrast to [[PropertyReflector]] which only introspects regular objects,
* this ObjectReader is also able to handle maps and arrays.
* For maps properties are key-pairs identified by string keys,
* For arrays properties are elements identified by integer index.
*
* This class has symmetric implementation across all languages supported
* by Pip.Services toolkit and used to support dynamic data processing.
*
* Because all languages have different casing and case sensitivity rules,
* this ObjectReader treats all property names as case insensitive.
*
* @see [[PropertyReflector]]
*
* ### Example ###
*
* let myObj = new MyObject();
*
* let properties = ObjectReader.getPropertyNames();
* ObjectReader.hasProperty(myObj, "myProperty");
* let value = PropertyReflector.getProperty(myObj, "myProperty");
*
* let myMap = { key1: 123, key2: "ABC" };
* ObjectReader.hasProperty(myMap, "key1");
* let value = ObjectReader.getProperty(myMap, "key1");
*
* let myArray = [1, 2, 3]
* ObjectReader.hasProperty(myArrat, "0");
* let value = ObjectReader.getProperty(myArray, "0");
*/
export declare class ObjectReader {
/**
* Gets a real object value.
* If object is a wrapper, it unwraps the value behind it.
* Otherwise it returns the same object value.
*
* @param obj an object to unwrap..
* @returns an actual (unwrapped) object value.
*/
static getValue(obj: any): any;
/**
* Checks if object has a property with specified name.
*
* The object can be a user defined object, map or array.
* The property name correspondently must be object property,
* map key or array index.
*
* @param obj an object to introspect.
* @param name a name of the property to check.
* @returns true if the object has the property and false if it doesn't.
*/
static hasProperty(obj: any, name: string): boolean;
/**
* Gets value of object property specified by its name.
*
* The object can be a user defined object, map or array.
* The property name correspondently must be object property,
* map key or array index.
*
* @param obj an object to read property from.
* @param name a name of the property to get.
* @returns the property value or null if property doesn't exist or introspection failed.
*/
static getProperty(obj: any, name: string): any;
/**
* Gets names of all properties implemented in specified object.
*
* The object can be a user defined object, map or array.
* Returned property name correspondently are object properties,
* map keys or array indexes.
*
* @param obj an objec to introspect.
* @returns a list with property names.
*/
static getPropertyNames(obj: any): string[];
/**
* Get values of all properties in specified object
* and returns them as a map.
*
* The object can be a user defined object, map or array.
* Returned properties correspondently are object properties,
* map key-pairs or array elements with their indexes.
*
* @param obj an object to get properties from.
* @returns a map, containing the names of the object's properties and their values.
*/
static getProperties(obj: any): any;
}