Question

我已按照教程：http://www.javascriptkit.com/dhtmltutors/live-local-time-google-time-zone-api.shtml

现在我想把它分成两个函数：
功能＃1。以毫秒为单位返回设置时区的当前时间
功能＃2。将函数＃1中的localdate对象每秒递增1秒，然后将其插入

但我得到输出＆＃34;无效日期＆＃34; 这是我的代码：

＆＃13;

var loc = '37.7749295, -122.4194155'; // San Francisco expressed as lat, lng tuple
	var targetDate = new Date(); // Current date/time of user computer
	var timestamp = targetDate.getTime() /1000 + targetDate.getTimezoneOffset() * 60; // Current UTC date/time expressed as seconds since midnight, January 1, 1970 UTC
	var apikey = 'Google_Time_Zone_key'; // timezone API key
	var apicall = 'https://maps.googleapis.com/maps/api/timezone/json?location=' + loc +'&timestamp=' + timestamp + '&key=' + apikey;

function current_time_load1 () {
	var xhr = new XMLHttpRequest (); // create new XMLHttpRequest2 object
	xhr.open ('GET', apicall); // open GET request
	xhr.onload = function() {
      	if (xhr.status === 200) { // if Ajax request successful
    		var output = JSON.parse(xhr.responseText); // convert returned JSON string to JSON object
         		// console.log(output.status); // log API return status for debugging purpose
        	if (output.status =='OK') { // if API reports everthing was returned sucessfully
    			var offsets = output.dstOffset * 1000 + output.rawOffset * 1000; // get DST and time zone offsets in milliseconds
    			var localdate = new Date (timestamp * 1000 + offsets); // Date object containing current time of destination (timestamp + dstOffset + rawOffset)
          			// localdate.toLocaleString(); // Display current destination date and time
          		var refreshDate = new Date(); // get current date again to calculate time elapsed between targetDate and now
                var millisecondselapsed = refreshDate - targetDate; // get amount of time elapsed between targetDate and now
                localdate.setMilliseconds(localdate.getMilliseconds()+ millisecondselapsed); // update localdate to account for any time elapsed
          		}
          }
			else { 
      	console.log ('Request failed. Returned status of ' + xhr.status);
			} //end of xhr.onload
		}
	xhr.send(); // send request 
	}

function current_time_load(divid){
  var container = document.getElementById(divid);
  var localdate = new Date (current_time_load1 ());
  setInterval(function(){
                    localdate.setSeconds(localdate.getSeconds()+1);
                    container.innerHTML = localdate.toLocaleTimeString('zh', {year : 'numeric', month: 'short', day: 'numeric'});
                }, 1000);
}
  
  current_time_load('time');

＆＃13;

<div>
test current time: <span id="time"></span>
</div>

＆＃13;

我确实在console.log中检查了current_time_load1（）的值，显示未定义，但是console.log（localdate.setMilliseconds（localdate.getMilliseconds（）+ millisecondselapsed）;）确实返回了毫秒

你能帮忙指出分裂的错误吗？

Answer 1

几个小时的搜索，我终于意识到它需要一个回调来检索XmlHttpRequest的结果。这对我有用：

function current_time_load1 (callback) {
	var xhr = new XMLHttpRequest (); // create new XMLHttpRequest2 object
	xhr.open ('GET', apicall); // open GET request
	xhr.onload = function() {
      	if (xhr.status === 200) { // if Ajax request successful
    		var output = JSON.parse(xhr.responseText); // convert returned JSON string to JSON object
         		// console.log(output.status); // log API return status for debugging purpose
        	if (output.status =='OK') { // if API reports everthing was returned sucessfully
    			var offsets = output.dstOffset * 1000 + output.rawOffset * 1000; // get DST and time zone offsets in milliseconds
    			var localdate = new Date (timestamp * 1000 + offsets); // Date object containing current time of destination (timestamp + dstOffset + rawOffset)
          			// localdate.toLocaleString(); // Display current destination date and time
          		var refreshDate = new Date(); // get current date again to calculate time elapsed between targetDate and now
                var millisecondselapsed = refreshDate - targetDate; // get amount of time elapsed between targetDate and now
                if(callback) { 
                    callback(localdate.setMilliseconds(localdate.getMilliseconds()+ millisecondselapsed));
                } // update localdate to account for any time elapsed
          	    //console.log(localdate.setMilliseconds(localdate.getMilliseconds()+ millisecondselapsed));
            }
          }
			else { 
      	console.log ('Request failed. Returned status of ' + xhr.status);
			} //end of xhr.onload
		}
	xhr.send(); // send request 
	}

  current_time_load1(function (result){
    console.log('okay');
  var container = document.getElementById('test');
  var localdate = new Date(result);
  setInterval(function(){
                    localdate.setSeconds(localdate.getSeconds()+1);
                    container.innerHTML = localdate.toLocaleTimeString('zh', {year : 'numeric', month: 'short', day: 'numeric'});
                }, 1000);
}, function(){
    console.log('fail');
  });

所以，我基本上将if(callback){callback();}添加到current_time_load1函数中。然后使用包含“result”参数的新函数运行此函数。一个很好的教训：）

我的日期字符串的日期问题无效

1 个答案: