Question

编辑：我怎么能这样做：

    tickets = [ 
{ date: "Jan 05,2016", time: "08:19 AM", name: "Bernie Sanders" },
{ date: "Jan 05,2016", time: "09:29 AM", name: "Donald Trump" },
{ date: "Jan 05,2016", time: "09:31 AM", name: "Donald Trump" },
{ date: "Jan 05,2016", time: "09:34 AM", name: "Donald Trump" },
{ date: "Jan 05,2016", time: "09:34 AM", name: "Bernie Sanders" },
{ date: "Jan 05,2016", time: "09:07 AM", name: "Mike Huckabee"}
];

    ...

到此：

tickets = [ 
{ date: "Jan 05,2016", time: "08:19 AM", name: "Bernie Sanders", total: 1 },
{ date: "Jan 05,2016", time: "09:29 AM", name: "Donald Trump", total: 1 },
{ date: "Jan 05,2016", time: "09:31 AM", name: "Donald Trump", total: 2 },
{ date: "Jan 05,2016", time: "09:34 AM", name: "Donald Trump", total: 3 },
{ date: "Jan 05,2016", time: "09:34 AM", name: "Bernie Sanders", total: 2 },
{ date: "Jan 05,2016", time: "09:07 AM", name: "Mike Huckabee", total: 1}
]

我查看了处理对象和数组的流行库。例如，underscore.js，lodash.js，lazy.js.我无法找到任何可以做到这一点的事情

Answer 1

假设您不需要支持旧版浏览器，vanillaJS拥有您需要的一切：

＆＃13;

tickets = [ 
  { date: "Jan 05,2016", time: "08:19 AM", name: "Bernie Sanders" },
  { date: "Jan 05,2016", time: "09:29 AM", name: "Donald Trump" },
  { date: "Jan 05,2016", time: "09:31 AM", name: "Donald Trump" },
  { date: "Jan 05,2016", time: "09:34 AM", name: "Donald Trump" },
  { date: "Jan 05,2016", time: "09:34 AM", name: "Bernie Sanders" },
  { date: "Jan 05,2016", time: "09:07 AM", name: "Mike Huckabee"}
];

var x = document.getElementById('x');

var runningTotals = {};

var addTotalToTicket = function(ticket){
  if ( ! (ticket.name in runningTotals ) ) {
    runningTotals[ticket.name] = 0;  
  }
  runningTotals[ticket.name]++;
  ticket.votes = runningTotals[ticket.name];
  return ticket;
};

var ticketsWithTotals = tickets.map(addTotalToTicket);

x.innerHTML = JSON.stringify(ticketsWithTotals,null,"  ");

＆＃13;

pre {
  background-color: #ded;
}

＆＃13;

<pre><code id="x"></code></pre>

＆＃13;

Answer 2

不是我的，但那就是你要找的东西：

// Source: http://www.bennadel.com/blog/1504-Ask-Ben-Parsing-CSV-Strings-With-Javascript-Exec-Regular-Expression-Command.htm
// This will parse a delimited string into an array of
// arrays. The default delimiter is the comma, but this
// can be overriden in the second argument.

function CSVToArray(strData, strDelimiter) {
    // Check to see if the delimiter is defined. If not,
    // then default to comma.
    strDelimiter = (strDelimiter || ",");
    // Create a regular expression to parse the CSV values.
    var objPattern = new RegExp((
    // Delimiters.
    "(\\" + strDelimiter + "|\\r?\\n|\\r|^)" +
    // Quoted fields.
    "(?:\"([^\"]*(?:\"\"[^\"]*)*)\"|" +
    // Standard fields.
    "([^\"\\" + strDelimiter + "\\r\\n]*))"), "gi");
    // Create an array to hold our data. Give the array
    // a default empty first row.
    var arrData = [[]];
    // Create an array to hold our individual pattern
    // matching groups.
    var arrMatches = null;
    // Keep looping over the regular expression matches
    // until we can no longer find a match.
    while (arrMatches = objPattern.exec(strData)) {
        // Get the delimiter that was found.
        var strMatchedDelimiter = arrMatches[1];
        // Check to see if the given delimiter has a length
        // (is not the start of string) and if it matches
        // field delimiter. If id does not, then we know
        // that this delimiter is a row delimiter.
        if (strMatchedDelimiter.length && (strMatchedDelimiter != strDelimiter)) {
            // Since we have reached a new row of data,
            // add an empty row to our data array.
            arrData.push([]);
        }
        // Now that we have our delimiter out of the way,
        // let's check to see which kind of value we
        // captured (quoted or unquoted).
        if (arrMatches[2]) {
            // We found a quoted value. When we capture
            // this value, unescape any double quotes.
            var strMatchedValue = arrMatches[2].replace(
            new RegExp("\"\"", "g"), "\"");
        } else {
            // We found a non-quoted value.
            var strMatchedValue = arrMatches[3];
        }
        // Now that we have our value string, let's add
        // it to the data array.
        arrData[arrData.length - 1].push(strMatchedValue);
    }
    // Return the parsed data.
    return (arrData);
}

function CSV2JSON(csv) {
    var array = CSVToArray(csv);
    var objArray = [];
    for (var i = 1; i < array.length; i++) {
        objArray[i - 1] = {};
        for (var k = 0; k < array[0].length && k < array[i].length; k++) {
            var key = array[0][k];
            objArray[i - 1][key] = array[i][k]
        }
    }

    var json = JSON.stringify(objArray);
    var str = json.replace(/},/g, "},\r\n");

    return str;
}

JSFiddle：

http://jsfiddle.net/sturtevant/AZFvQ/

Answer 3

假设您想获得某人的条目总数，您可以使用underscore.js groupBy()和reduce()函数

CSV格式到具有运行总计的对象数组

3 个答案: