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Node.js之Console用法小结
/**
 * Created by city--online on 16/3/9.
 */

//console.time()和console.timeEnd()输出中间代码的执行时间(注意:time和timeEnd的参数必须完全一致)
console.time("hello");

console.log("hello world");

//依次序输出所有字符串
console.log("%s","Hello" ,"World");

//将对象转换为普通字符串后执行
console.log("%s","cuiyanwei",{name:"小崔"});

//将字符串作为数值进行转换
console.log("%d","25.6");
console.log("%d","cuiyanwei");

// 输出%
console.log("%%");

console.log("%%","cyw");

//console.warn的用法和console.error()用法一样
//console.error("this  is error");

//console.trace()方法将当前位置处的栈信息作为标准错误信息进行输出.
var obj={
    name:"cuiyanwei",
    age:24,
    eat:function(){

    }
}
console.trace(obj);

//查看对象里的内容并输出:
console.dir(obj);


//显示所有nodejs中的全局变量、函数、对象:
console.log(global);

//console.assert()对表达式结果进行评估,如果该表达式的执行结果为false,则输出一个消息字符串并抛出AssertionError异常
console.assert(2==1,"error 2==1");


console.timeEnd("hello");

 

/usr/local/bin/node Console.js
hello world
Hello World
cuiyanwei { name: '小崔' }
25.6
NaN
%%
% cyw
Trace: { name: 'cuiyanwei', age: 24, eat: [Function] }
    at Object.<anonymous> (/Users/city--online/Desktop/Console/Console.js:37:9)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Function.Module.runMain (module.js:441:10)
    at startup (node.js:134:18)
    at node.js:962:3
Trace: a
    at Object.<anonymous> (/Users/city--online/Desktop/Console/Console.js:39:9)
    at Module._compile (module.js:409:26)
    at Object.Module._extensions..js (module.js:416:10)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Function.Module.runMain (module.js:441:10)
    at startup (node.js:134:18)
    at node.js:962:3
{ name: 'cuiyanwei', age: 24, eat: [Function] }
{ DTRACE_NET_SERVER_CONNECTION: [Function],
  DTRACE_NET_STREAM_END: [Function],
  DTRACE_HTTP_SERVER_REQUEST: [Function],
  DTRACE_HTTP_SERVER_RESPONSE: [Function],
  DTRACE_HTTP_CLIENT_REQUEST: [Function],
  DTRACE_HTTP_CLIENT_RESPONSE: [Function],
  global: [Circular],
  process: 
   process {
     title: '/usr/local/bin/node',
     version: 'v4.3.1',
     moduleLoadList: 
      [ 'Binding contextify',
        'Binding natives',
        'NativeModule events',
        'NativeModule buffer',
        'Binding buffer',
        'NativeModule internal/util',
        'Binding util',
        'NativeModule timers',
        'Binding timer_wrap',
        'NativeModule _linklist',
        'NativeModule assert',
        'NativeModule util',
        'Binding uv',
        'NativeModule path',
        'NativeModule module',
        'NativeModule internal/module',
        'NativeModule vm',
        'NativeModule fs',
        'Binding fs',
        'NativeModule constants',
        'Binding constants',
        'NativeModule stream',
        'NativeModule _stream_readable',
        'NativeModule _stream_writable',
        'NativeModule _stream_duplex',
        'NativeModule _stream_transform',
        'NativeModule _stream_passthrough',
        'Binding fs_event_wrap',
        'NativeModule console',
        'Binding tty_wrap',
        'NativeModule net',
        'Binding cares_wrap',
        'Binding tcp_wrap',
        'Binding pipe_wrap',
        'Binding stream_wrap' ],
     versions: 
      { http_parser: '2.5.2',
        node: '4.3.1',
        v8: '4.5.103.35',
        uv: '1.8.0',
        zlib: '1.2.8',
        ares: '1.10.1-DEV',
        icu: '56.1',
        modules: '46',
        openssl: '1.0.2f' },
     arch: 'x64',
     platform: 'darwin',
     release: 
      { name: 'node',
        lts: 'Argon',
        sourceUrl: 'https://nodejs.org/download/release/v4.3.1/node-v4.3.1.tar.gz',
        headersUrl: 'https://nodejs.org/download/release/v4.3.1/node-v4.3.1-headers.tar.gz' },
     argv: 
      [ '/usr/local/bin/node',
        '/Users/city--online/Desktop/Console/Console.js' ],
     execArgv: [],
     env: 
      { SHELL: '/bin/bash',
        TMPDIR: '/var/folders/65/m0mbnd5515v0k2bnh6pzl75w0000gn/T/',
        __CF_USER_TEXT_ENCODING: '0x1F5:0x19:0x34',
        PATH: '/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin',
        VERSIONER_PYTHON_VERSION: '2.7',
        XPC_FLAGS: '0x0',
        USER: 'city--online',

        HOME: '/Users/city--online',
assert.js:89
        LOGNAME: 'city--online',
  throw new assert.AssertionError({
        XPC_SERVICE_NAME: '0',
  ^
        Apple_PubSub_Socket_Render: '/private/tmp/com.apple.launchd.BNOh3IvDtv/Render',
AssertionError: error 2==1
        SSH_AUTH_SOCK: '/private/tmp/com.apple.launchd.30OLhAehof/Listeners',
    at Console.assert (console.js:87:23)
        VERSIONER_PYTHON_PREFER_32_BIT: 'no' },
    at Object.<anonymous> (/Users/city--online/Desktop/Console/Console.js:46:9)
     pid: 5236,
    at Module._compile (module.js:409:26)
     features: 
    at Object.Module._extensions..js (module.js:416:10)
      { debug: false,
    at Module.load (module.js:343:32)
        uv: true,
    at Function.Module._load (module.js:300:12)
        ipv6: true,
    at Function.Module.runMain (module.js:441:10)
        tls_npn: true,
    at startup (node.js:134:18)
        tls_sni: true,
    at node.js:962:3
        tls_ocsp: true,
        tls: true },
     _needImmediateCallback: false,
     execPath: '/usr/local/bin/node',
     debugPort: 5858,
     _startProfilerIdleNotifier: [Function: _startProfilerIdleNotifier],
     _stopProfilerIdleNotifier: [Function: _stopProfilerIdleNotifier],
     _getActiveRequests: [Function: _getActiveRequests],
     _getActiveHandles: [Function: _getActiveHandles],
     reallyExit: [Function: reallyExit],
     abort: [Function: abort],
     chdir: [Function: chdir],
     cwd: [Function: cwd],
     umask: [Function: umask],
     getuid: [Function: getuid],
     geteuid: [Function: geteuid],
     setuid: [Function: setuid],
     seteuid: [Function: seteuid],
     setgid: [Function: setgid],
     setegid: [Function: setegid],
     getgid: [Function: getgid],
     getegid: [Function: getegid],
     getgroups: [Function: getgroups],
     setgroups: [Function: setgroups],
     initgroups: [Function: initgroups],
     _kill: [Function: _kill],
     _debugProcess: [Function: _debugProcess],
     _debugPause: [Function: _debugPause],
     _debugEnd: [Function: _debugEnd],
     hrtime: [Function: hrtime],
     dlopen: [Function: dlopen],
     uptime: [Function: uptime],
     memoryUsage: [Function: memoryUsage],
     binding: [Function: binding],
     _linkedBinding: [Function: _linkedBinding],
     _setupDomainUse: [Function: _setupDomainUse],
     _events: { newListener: [Function], removeListener: [Function] },
     _rawDebug: [Function],
     domain: null,
     _maxListeners: undefined,
     EventEmitter: 
      { [Function: EventEmitter]
        EventEmitter: [Circular],
        usingDomains: false,
        defaultMaxListeners: 10,
        init: [Function],
        listenerCount: [Function] },
     _fatalException: [Function],
     _exiting: false,
     assert: [Function],
     config: { target_defaults: [Object], variables: [Object] },
     nextTick: [Function: nextTick],
     _tickCallback: [Function: _tickCallback],
     _tickDomainCallback: [Function: _tickDomainCallback],
     stdout: [Getter],
     stderr: [Getter],
     stdin: [Getter],
     openStdin: [Function],
     exit: [Function],
     kill: [Function],
     _eventsCount: NaN,
     mainModule: 
      Module {
        id: '.',
        exports: {},
        parent: null,
        filename: '/Users/city--online/Desktop/Console/Console.js',
        loaded: false,
        children: [],
        paths: [Object] } },
  GLOBAL: [Circular],
  root: [Circular],
  Buffer: 
   { [Function: Buffer]
     poolSize: 8192,
     isBuffer: [Function: isBuffer],
     compare: [Function: compare],
     isEncoding: [Function],
     concat: [Function],
     byteLength: [Function: byteLength] },
  clearImmediate: [Function],
  clearInterval: [Function],
  clearTimeout: [Function],
  setImmediate: [Function],
  setInterval: [Function],
  setTimeout: [Function],
  console: [Getter] }

Process finished with exit code 1

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