如何一次循环 100 个?

Question

Google api一次只允许我获取100个符号。如何循环它，使其获得 100 个交易品种，然后是下一个 100 个品种，而无需为每 100 个股票制作一个新脚本？或者，有没有更好的方法可以做到这一点？

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script>
$.getJSON('https://www..com/api/public/user/token/exchange_stocks/NYSE', function(data) {
var stocks = "";
for (var n = 0; n < 250; n++)
{
console.log(data[n]["symbol"]);
stocks += (data[n]["symbol"] +",");
stocks = stocks.replace(/[.]/g, "");
}

var temp = [];
$(document).ready(function(){
stockInformation();
setInterval(stockInformation, 5000);
});
function stockInformation()
{
$.ajax({
url:"http://finance.google.com/finance/info?client=ig&q=NYSE:" + stocks,
dataType:"jsonp",
jsonp:"callback",
jsonpCallback:"quote"
});
var i = 0; var j = 0;var status = "";
quote = function(data){
var output = "<table>"
$.each(data, function(key, value){
if (value.l_cur > temp[j])
status = "<td style=color:green>Up</td>";
else if (value.l_cur < temp[j])
status = "<td style=color:red>Down</td>";
else
status = "<td>Same</td>";
j++;
output += "<tr><td>" + value.t + "</td><td>" + value.l_cur + "</td><td>" + value.c + "</td><td>" + value.cp + "</td>" + status + "</tr>";
temp[i] = value.l_cur;i++;
})
output += "</table>";
$("#result").html(output);
}
}
});
</script>

<div id="container">
<div id="result"></div>
</div>

Answer 1

我建议你将股票名称分成 100 个块，发出partitions.length请求并使用$.when等待所有请求完成。下面是一个未经测试的示例：

$.getJSON('https://www..com/api/public/user/token/exchange_stocks/NYSE').then(function(data) {
var partitions = [];
var stocks = "";
for (var n = 0; n < 250; n++) {
// if n is divisible by 100, push current stocks into partition
// and empty stocks string
if (n % 100 === 0) {
partitions.push(stocks)
stocks = ""
continue
}
console.log(data[n]["symbol"]);
stocks += (data[n]["symbol"] +",");
stocks = stocks.replace(/[.]/g, "");
}
// make all requests and store their $.Deferred in an array
var requests = partitions.map(function(stockSymbols) {
return $.getJSON("http://finance.google.com/finance/info?client=ig&q=NYSE:" + stockSymbols);
});
// wait for all requests to complete
$.when.apply($, requests)
.done(function() {
var allStockData = [];
for (var i = 0; i < arguments.length; i++) {
// each argument to the done callback is a response 
// formatted: [ data, statusText, jqXHR ]
// concat the data to our collection of responses
allStockData = allStockData.concat(arguments[i][0])
}
// do your table stuff with allStockData here
})
})

Answer 2

我在想下面这样的事情。 这是完全未经测试的，但至少也许它会给你一些想法。

$.getJSON('https://www..com/api/public/user/token/exchange_stocks/NYSE', function(data) {
var temp = [];
var sympols = {};
//get an array of all the symbols, removing the periods
var stocks = $.map(data, function(stock){
return stock.symbol.replace(/[.]/g, "");
});
//if there are more than 250, get just the first 250
if (stocks.length > 250) stocks = stocks.slice(0, 250);
//preload the symbols map
$.each(stocks, function(stock){
//default prices to 0
symbols[stock] = 0;
});
//join them into a comma separated string
stocks = stocks.join(',');
(function updateShortList(shortlist){
if (shortlist.length > 100) {
//send just the first 100
var $deferred = stockInformation(shortlist.slice(0, 100));
//repeat function without the stocks previously processed
$deferred.then(function(){ updateShortList(shortlist.slice(100)); });
} else {
//send them all
var $deferred = stockInformation(shortlist);
//wait 5 seconds before starting over
$deferred.then(function(){
//after 5 seconds, build the results, and send all the stocks again
setTimeout(function(){
//put all the accumulated results to the page
$("#result").html('<table>'+ temp.join('') +'</table>');
//clear the results
temp = [];
//start over
updateShortList(stocks);
}, 5000);
});
}
})(stocks);
function stockInformation(stocks) {
var quote = function(data) {
var status = "";
var output = "";
$.each(data, function(key, value) {
//compare old ticker value to new ticker value
if (value.l_cur > symbols[value.t])
status = "<td style=color:green>Up</td>";
else if (value.l_cur < symbols[value.t])
status = "<td style=color:red>Down</td>";
else
status = "<td>Same</td>";
//update the stored ticker value
symbols[value.t] = value.l_cur;
//add the row to the results collection
temp.push("<tr><td>" + value.t + "</td><td>" + value.l_cur + "</td><td>" + value.c + "</td><td>" + value.cp + "</td>" + status + "</tr>");
});
}
return $.ajax({
url: "http://finance.google.com/finance/info?client=ig&q=NYSE:" + stocks,
dataType: "jsonp",
jsonp: "callback",
jsonpCallback: "quote"
});
}
});