如何使用JavaScript从*.CSV文件读取数据?

我的CSV数据是这样的:

heading1,heading2,heading3,heading4,heading5
value1_1,value2_1,value3_1,value4_1,value5_1
value1_2,value2_2,value3_2,value4_2,value5_2
...

如何使用JavaScript读取数据并将其转换为这样的数组?：

[
    heading1: value1_1,
    heading2: value2_1,
    heading3: value3_1,
    heading4: value4_1
    heading5: value5_1
],[
    heading1: value1_2,
    heading2: value2_2,
    heading3: value3_2,
    heading4: value4_2,
    heading5: value5_2
]
....

我试过这个代码，但运气不好!：

<script type="text/javascript">
    var allText =[];
    var allTextLines = [];
    var Lines = [];

    var txtFile = new XMLHttpRequest();
    txtFile.open("GET", "file://d:/data.txt", true);
    txtFile.onreadystatechange = function()
    {
        allText = txtFile.responseText;
        allTextLines = allText.split(/\r\n|\n/);
    };

    document.write(allTextLines);
    document.write(allText);
    document.write(txtFile);
</script>

当前回答

下面是另一种将外部CSV读入Javascript的方法(使用jQuery)。

它有点冗长，但我觉得通过将数据读入数组，您可以准确地遵循这个过程，并使故障排除变得容易。

也许能帮到别人。

数据文件示例:

Time,data1,data2,data2
08/11/2015 07:30:16,602,0.009,321

下面是代码:

$(document).ready(function() {
 // AJAX in the data file
    $.ajax({
        type: "GET",
        url: "data.csv",
        dataType: "text",
        success: function(data) {processData(data);}
        });

    // Let's process the data from the data file
    function processData(data) {
        var lines = data.split(/\r\n|\n/);

        //Set up the data arrays
        var time = [];
        var data1 = [];
        var data2 = [];
        var data3 = [];

        var headings = lines[0].split(','); // Splice up the first row to get the headings

        for (var j=1; j<lines.length; j++) {
        var values = lines[j].split(','); // Split up the comma seperated values
           // We read the key,1st, 2nd and 3rd rows 
           time.push(values[0]); // Read in as string
           // Recommended to read in as float, since we'll be doing some operations on this later.
           data1.push(parseFloat(values[1])); 
           data2.push(parseFloat(values[2]));
           data3.push(parseFloat(values[3]));

        }

    // For display
    var x= 0;
    console.log(headings[0]+" : "+time[x]+headings[1]+" : "+data1[x]+headings[2]+" : "+data2[x]+headings[4]+" : "+data2[x]);
    }
})

希望这对将来的人有所帮助!

2015-08-13 12:35:56

其他回答

注意:在我被提醒有效CSV文件中可能出现的所有“特殊情况”(如转义引号)之前，我制定了这个解决方案。我把我的答案留给那些想要快速和肮脏的东西的人，但为了准确起见，我推荐Evan的答案。

当你的data.txt文件是一个用逗号分隔的长字符串，没有换行符时，这段代码将正常工作:

data.txt:

 heading1,heading2,heading3,heading4,heading5,value1_1,...,value5_2

javascript:

$(document).ready(function() {
    $.ajax({
        type: "GET",
        url: "data.txt",
        dataType: "text",
        success: function(data) {processData(data);}
     });
});

function processData(allText) {
    var record_num = 5;  // or however many elements there are in each row
    var allTextLines = allText.split(/\r\n|\n/);
    var entries = allTextLines[0].split(',');
    var lines = [];

    var headings = entries.splice(0,record_num);
    while (entries.length>0) {
        var tarr = [];
        for (var j=0; j<record_num; j++) {
            tarr.push(headings[j]+":"+entries.shift());
        }
        lines.push(tarr);
    }
    // alert(lines);
}

下面的代码将工作在一个“真正的”CSV文件，每组记录之间的换行:

data.txt:

heading1,heading2,heading3,heading4,heading5
value1_1,value2_1,value3_1,value4_1,value5_1
value1_2,value2_2,value3_2,value4_2,value5_2

javascript:

$(document).ready(function() {
    $.ajax({
        type: "GET",
        url: "data.txt",
        dataType: "text",
        success: function(data) {processData(data);}
     });
});

function processData(allText) {
    var allTextLines = allText.split(/\r\n|\n/);
    var headers = allTextLines[0].split(',');
    var lines = [];

    for (var i=1; i<allTextLines.length; i++) {
        var data = allTextLines[i].split(',');
        if (data.length == headers.length) {

            var tarr = [];
            for (var j=0; j<headers.length; j++) {
                tarr.push(headers[j]+":"+data[j]);
            }
            lines.push(tarr);
        }
    }
    // alert(lines);
}

http://jsfiddle.net/mblase75/dcqxr/

2011-09-15 13:21:14

使用csvToObjs函数，您可以将数据条目从CSV格式转换为对象数组。

function csvToObjs(string) { const lines = data.split(/\r\n|\n/); let [headings, ...entries] = lines; headings = headings.split(','); const objs = []; entries.map(entry=>{ obj = entry.split(','); objs.push(Object.fromEntries(headings.map((head, i)=>[head, obj[i]]))); }) return objs; } data = `heading1,heading2,heading3,heading4,heading5 value1_1,value2_1,value3_1,value4_1,value5_1 value1_2,value2_2,value3_2,value4_2,value5_2` console.log(csvToObjs(data));

2021-09-20 16:29:12

下面是一个JavaScript函数，用于解析CSV数据，计算引号内的逗号。

// Parse a CSV row, accounting for commas inside quotes                   
function parse(row){
  var insideQuote = false,                                             
      entries = [],                                                    
      entry = [];
  row.split('').forEach(function (character) {                         
    if(character === '"') {
      insideQuote = !insideQuote;                                      
    } else {
      if(character == "," && !insideQuote) {                           
        entries.push(entry.join(''));                                  
        entry = [];                                                    
      } else {
        entry.push(character);                                         
      }                                                                
    }                                                                  
  });
  entries.push(entry.join(''));                                        
  return entries;                                                      
}

函数解析CSV文件的示例如下:

"foo, the column",bar
2,3
"4, the value",5

数组:

// csv could contain the content read from a csv file
var csv = '"foo, the column",bar\n2,3\n"4, the value",5',

    // Split the input into lines
    lines = csv.split('\n'),

    // Extract column names from the first line
    columnNamesLine = lines[0],
    columnNames = parse(columnNamesLine),

    // Extract data from subsequent lines
    dataLines = lines.slice(1),
    data = dataLines.map(parse);

// Prints ["foo, the column","bar"]
console.log(JSON.stringify(columnNames));

// Prints [["2","3"],["4, the value","5"]]
console.log(JSON.stringify(data));

下面是如何将数据转换为对象，就像D3的csv解析器(这是一个可靠的第三方解决方案):

var dataObjects = data.map(function (arr) {
  var dataObject = {};
  columnNames.forEach(function(columnName, i){
    dataObject[columnName] = arr[i];
  });
  return dataObject;
});

// Prints [{"foo":"2","bar":"3"},{"foo":"4","bar":"5"}]
console.log(JSON.stringify(dataObjects));

这是这段代码的工作原理。

享受吧!——伦

2014-04-03 23:23:38

我使用d3.js解析csv文件。非常容易使用。这是文件。

步骤:

NPM安装d3-request

使用Es6;

import { csv } from 'd3-request';
import url from 'path/to/data.csv';

csv(url, function(err, data) {
 console.log(data);
})

请参阅医生了解更多信息。

更新- - - D3-request已弃用。你可以使用d3-fetch

2017-12-25 14:22:29