CrossBrowdy - Basic tutorial

Data

Objects and JSON

Here is an example of objects and JSON management:


	//Defines a "class" and creates an instance of it with 3 properties (1 of them inherited through the prototype):
	var myClass = function() {};
	myClass.prototype.propertyInherited = "propertyInherited_value"; //Adds the "propertyInherited" property to the prototype.
	var myObject = new myClass(); //Creates an instance of 'myClass'.
	myObject.property1 = "property1_value"; //Adds the "property1" property to the object.
	myObject.property2 = { "subproperty1" : "subproperty1_value" }; //Adds the "property2" property to the object.
	
	//Getting the size of the object, just counting properties on the first level (equivalent to 'CB_sizeof', 'CB_Arrays.sizeOf' and 'CB_Arrays.sizeof'):
	var myObjectSize = CB_sizeOf(myObject); //Also counts not own properties, inherited from prototype. Returns: 3.
	var myObjectSize_2 = CB_sizeOf(myObject, true); //Only counts own properties, not inherited from prototype. Returns: 2.

	//Duplicating an object:
	var objectCopy = CB_copyObject({"hello" : "world", "whatever" : 123, "subObject" : { "subObject2" : "hello" } }); //Returns another object with the same properties and their values (copies it).

	//Combines two objects, third parameter ignored when not using two arrays (equivalent to 'CB_combineJSON' and 'CB_Arrays.combine'):
	var objectsCombined = CB_combineArraysOrObjects({ a : 1, b: 2, c: 3 }, { c : 4, d : 5 }); //Returns the object: { a: 1, b: 2, c: 4, d: 5 }.
	var objectsCombined_2 = CB_combineArraysOrObjects({ c : 4, d : 5 }, { a : 1, b: 2, c: 3 }); //Returns the object: { c: 3, d: 5, a: 1, b: 2 }.
	var objectsCombined_3 = CB_combineArraysOrObjects({ a : 1, b: 2, c: 3 }, { c : 4, d : 5 }, true); //Returns the same as 'objectsCombined'.
	var objectsCombined_4 = CB_combineArraysOrObjects({ c : 4, d : 5 }, { a : 1, b: 2, c: 3 }, true); //Returns the same as 'objectsCombined_2'.

	//Combines one array with one object, third parameter ignored when not using two arrays (equivalent to 'CB_combineJSON' and 'CB_Arrays.combine'):
	var objectsCombined_5 = CB_combineArraysOrObjects([1, 2, 3], { 1 : 22, "index1" : "3", "index2" : "whatever", "index3" : 3 }); //Returns the object: { 0: 1, 1: 22, 2: 3, index1: "3", index2: "whatever", index3: 3 }.
	var objectsCombined_6 = CB_combineArraysOrObjects({ 1 : 22, "index1" : "3", "index2" : "whatever", "index3" : 3 }, [1, 2, 3]); //Returns the object: { 0: 1, 1: 2, 2: 3, index1: "3", index2: "whatever", index3: 3 }.
	var objectsCombined_7 = CB_combineArraysOrObjects([1, 2, 3], { 1 : 22, "index1" : "3", "index2" : "whatever", "index3" : 3 }, true); //Returns the same as 'objectsCombined_5'.
	var objectsCombined_8 = CB_combineArraysOrObjects({ 1 : 22, "index1" : "3", "index2" : "whatever", "index3" : 3 }, [1, 2, 3], true); //Returns the same as 'objectsCombined_6'.
	
	//Here is a way to get the value inside a given index from a desired object, returning the desired value if not found:
	//NOTE: when dealing with strings, 'CB_getValuePath' can be a better option.
	var JSONObject = { "name" : "CrossBrowdy", "locations" : { "first" : "Wonderland" } };
	var name = CB_getValueIndex(JSONObject, "name"); //Returns "CrossBrowdy".
	var locations = CB_getValueIndex(JSONObject, "locations"); //Returns { "first" : "Wonderland" }.
	var locationsFirst = CB_getValueIndex(JSONObject["locations"], "first"); //Returns "Wonderland".
	var locationsSecond = CB_getValueIndex(JSONObject["locations"], "second"); //Returns undefined.
	var locationsSecond_2 = CB_getValueIndex(JSONObject["locations"], "second", "Value when not found"); //Returns "Value when not found".

	//It is possible to parse a string that contains a JSON object to create a real JSON object and vice versa:
	//NOTE: internally, 'CB_parseJSON' uses 'JSON.parse' and 'CB_stringifyJSON' uses 'JSON.stringify'. If they are not available natively, a fallback method will be chosen automatically.
	var JSONObject = { a : 1, "b" : { "c" : "hello" } };
	var JSONObjectString = CB_stringifyJSON(JSONObject); //Returns a string containing 'JSONObject'. Second and third parameters would be used as the second and third ones ("replacer" and "space") when calling 'JSON.stringify' internally.
	var JSONObject_2 = CB_parseJSON(JSONObjectString); //Contains the same as 'JSONObject'. Second parameter would be used as the second one ("reviver") when calling 'JSON.parse' internally.
	var JSONObject_3 = CB_parseJSON(123, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns 123 (number).
	var JSONObject_4 = CB_parseJSON(123, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns the same as 'JSONObject_3'.
	var JSONObject_5 = CB_parseJSON("not_a_JSON_object", undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObject_6 = CB_parseJSON("not_a_JSON_object", undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObject_7 = CB_parseJSON(function(){}, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObject_8 = CB_parseJSON(function(){}, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObject_9 = CB_parseJSON(NaN, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObject_10 = CB_parseJSON(NaN, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObject_11 = CB_parseJSON(null, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns an empty object.
	var JSONObject_12 = CB_parseJSON(null, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns null.
	var JSONObject_13 = CB_parseJSON(undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns an empty object.
	var JSONObject_14 = CB_parseJSON(undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns "error_value" and calls the error callback.
	var JSONObjectString_2 = CB_stringifyJSON(123, undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "123" (string).
	var JSONObjectString_3 = CB_stringifyJSON(123, undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns the same as 'JSONObjectString_2'.
	var JSONObjectString_4 = CB_stringifyJSON("one_string", undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "\"one_string\"".
	var JSONObjectString_5 = CB_stringifyJSON("one_string", undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns the same as 'JSONObjectString_4'.
	var JSONObjectString_6 = CB_stringifyJSON(function(){}, undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value".
	var JSONObjectString_7 = CB_stringifyJSON(function(){}, undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns undefined.
	var JSONObjectString_8 = CB_stringifyJSON(NaN, undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value".
	var JSONObjectString_9 = CB_stringifyJSON(NaN, undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns "null" (string).
	var JSONObjectString_10 = CB_stringifyJSON(null, undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value".
	var JSONObjectString_11 = CB_stringifyJSON(null, undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns "null" (string).
	var JSONObjectString_12 = CB_stringifyJSON(undefined, undefined, undefined, "error_value", true, function() { CB_console("Failed!"); }); //Returns "error_value".
	var JSONObjectString_13 = CB_stringifyJSON(undefined, undefined, undefined, "error_value", false, function() { CB_console("Failed!"); }); //Returns undefined.
	
	//The 'CB_getJSONPropertyValue' function is similar to 'CB_getValueIndex' but it will accept strings (it will try to parse them as JSON objects) and will return the element given again if the property is not given:
	var myValue = CB_getJSONPropertyValue(JSONObject, "a"); //Returns 1.
	var myValue_2 = CB_getJSONPropertyValue(JSONObject, "a", "not found"); //Returns the same as 'myValue'.
	var myValue_3 = CB_getJSONPropertyValue(JSONObject, "c"); //The "c" property cannot be found in the first level. Returns undefined.
	var myValue_4 = CB_getJSONPropertyValue(JSONObject, "c", "not found"); //The "c" property cannot be found in the first level. Returns "not found".
	var myValue_5 = CB_getJSONPropertyValue(JSONObjectString, "a"); //Returns the same as 'myValue'.
	var myValue_6 = CB_getJSONPropertyValue(JSONObjectString, "a", "not found"); //Returns the same as 'myValue'.
	var myValue_7 = CB_getJSONPropertyValue(JSONObjectString, "c"); //Returns the same as 'myValue_3'.
	var myValue_8 = CB_getJSONPropertyValue(JSONObjectString, "c", "not found"); //Returns the same as 'myValue_4'.

Note that the JSON object and its methods (as JSON.parse and JSON.stringify) will always be present, using polyfills internally automatically if it is not supported natively.

Check the API documentation to read more about some global functions and variables.

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CrossBrowdy by Joan Alba Maldonado