Cocos Creator record seven - Global Variables

Global Variables

Since all plug-in scripts are guaranteed to be loaded before the normal script, then in addition to load plug-ins, you can also use this feature to declare some special global variables. You can add a script in the project, and set the "Import to plug-in":

/ * * Globals.js /

// 定义新建组件的默认值
window.DEFAULT_IP = "192.168.1.1";

// 定义组件开关
window.ENABLE_NET_DEBUGGER = true;

// 定义引擎 API 缩写（仅适用于构造函数）
window.V2 = cc.Vec2;
接下来你就能在任意的普通脚本中直接访问它们：

/* network.js */

cc.Class({
    extends: cc.Component,
    properties: {
        ip: {
            default: DEFAULT_IP
        }
    }
});
/* network_debugger.js */

if (ENABLE_NET_DEBUGGER) {
    // ENABLE_NET_DEBUGGER 时这个组件才生效
    cc.Class({
        extends: cc.Component,
        properties: {
            location: {
                default: new V2(100, 200)
            }
        },
        update: function () {
            ...
        },
    });
}
else {
    // 否则这个组件什么也不做
    cc.Class({
        extends: cc.Component,
        start: function () {
            // 在开始后就移除该组件
            this.destroy();
        }
    });
}

Standard network interface

In Cocos Creator, we support standard network interfaces on the Web platform the most widely used:

XMLHttpRequest: for short connection
WebSocket: for a long connection
, of course, the Web platform, gifted with the original browser supports both interfaces, the reason that Cocos Creator support, because when you publish a native version, users of these two network interfaces the code also can run. That is to follow, "a source, multi-platform" has been adhering to the principle of Cocos.

Instructions

XMLHttpRequest 简单示例：

 var xhr = new XMLHttpRequest();
 xhr.onreadystatechange = function () {
     if (xhr.readyState == 4 && (xhr.status >= 200 && xhr.status < 400)) {
         var response = xhr.responseText;
         console.log(response);
     }
 };
 xhr.open("GET", url, true);
 xhr.send();

Developers can directly use the new XMLHttpRequest () to create a connection object, it can also be created by cc.loader.getXMLHttpRequest (), both consistent effect.

Refer to the document standard XMLHttpRequest MDN Chinese documents .

WebSocket

A simple example:

 ws = new WebSocket("ws://echo.websocket.org");
 ws.onopen = function (event) {
     console.log("Send Text WS was opened.");
 };
 ws.onmessage = function (event) {
     console.log("response text msg: " + event.data);
 };
 ws.onerror = function (event) {
     console.log("Send Text fired an error");
 };
 ws.onclose = function (event) {
     console.log("WebSocket instance closed.");
 };

 setTimeout(function () {
     if (ws.readyState === WebSocket.OPEN) {
         ws.send("Hello WebSocket, I'm a text message.");
     }
     else {
         console.log("WebSocket instance wasn't ready...");
     }
 }, 3);

WebSocket standard document, please refer MDN Chinese documents .