将JavaScript数组转换为逗号分隔列表的简便方法？

Question

我在JavaScript中有一个一维的字符串数组,我想把它变成以逗号分隔的列表.在花园种类的JavaScript(或jQuery)中有一种简单的方法可以将其转换为以逗号分隔的列表吗？(我知道如何迭代数组并通过连接自己构建字符串,如果这是唯一的方法.)

Answer 1

所述Array.prototype.join()方法:

var arr = ["Zero", "One", "Two"];

document.write(arr.join(", "));

Answer 2

实际上,toString()默认情况下,实现使用逗号连接:

var arr = [ 42, 55 ];
var str1 = arr.toString(); // Gives you "42,55"
var str2 = String(arr); // Ditto

我不知道这是否是JS规范的强制要求,但这是什么 最 几乎所有的浏览器似乎都在做.

Answer 3

简单数组

let simpleArray = [1,2,3,4]
let commaSeperated = simpleArray.join(",");
console.log(commaSeperated);

具有以逗号分隔的特定属性的对象数组。

let arrayOfObjects = [
{
id : 1,
name : "Name 1",
address : "Address 1"
},
{
id : 2,
name : "Name 2",
address : "Address 2"
},
{
id : 3,
name : "Name 3",
address : "Address 3"
}]
let names = arrayOfObjects.map(x => x.name).join(", ");
console.log(names);

结果

Name 1, Name 2, Name 3

Answer 4

或者(更有效率):

var arr = new Array(3);
arr[0] = "Zero";
arr[1] = "One";
arr[2] = "Two";

document.write(arr); // same as document.write(arr.toString()) in this context

调用时数组的toString方法完全返回所需内容 - 以逗号分隔的列表.

Answer 5

这是一个将二维数组或列数组转换为正确转义的CSV字符串的实现.这些函数不检查有效的字符串/数字输入或列数(确保您的数组有效开始).单元格可以包含逗号和引号!

这是一个用于解码CSV字符串的脚本.

这是我编码CSV字符串的脚本:

// Example
var csv = new csvWriter();
csv.del = '\t';
csv.enc = "'";

var nullVar;
var testStr = "The comma (,) pipe (|) single quote (') double quote (\") and tab (\t) are commonly used to tabulate data in plain-text formats.";
var testArr = [
    false,
    0,
    nullVar,
    // undefinedVar,
    '',
    {key:'value'},
];

console.log(csv.escapeCol(testStr));
console.log(csv.arrayToRow(testArr));
console.log(csv.arrayToCSV([testArr, testArr, testArr]));

/**
 * Class for creating csv strings
 * Handles multiple data types
 * Objects are cast to Strings
 **/

function csvWriter(del, enc) {
    this.del = del || ','; // CSV Delimiter
    this.enc = enc || '"'; // CSV Enclosure

    // Convert Object to CSV column
    this.escapeCol = function (col) {
        if(isNaN(col)) {
            // is not boolean or numeric
            if (!col) {
                // is null or undefined
                col = '';
            } else {
                // is string or object
                col = String(col);
                if (col.length > 0) {
                    // use regex to test for del, enc, \r or \n
                    // if(new RegExp( '[' + this.del + this.enc + '\r\n]' ).test(col)) {

                    // escape inline enclosure
                    col = col.split( this.enc ).join( this.enc + this.enc );

                    // wrap with enclosure
                    col = this.enc + col + this.enc;
                }
            }
        }
        return col;
    };

    // Convert an Array of columns into an escaped CSV row
    this.arrayToRow = function (arr) {
        var arr2 = arr.slice(0);

        var i, ii = arr2.length;
        for(i = 0; i < ii; i++) {
            arr2[i] = this.escapeCol(arr2[i]);
        }
        return arr2.join(this.del);
    };

    // Convert a two-dimensional Array into an escaped multi-row CSV 
    this.arrayToCSV = function (arr) {
        var arr2 = arr.slice(0);

        var i, ii = arr2.length;
        for(i = 0; i < ii; i++) {
            arr2[i] = this.arrayToRow(arr2[i]);
        }
        return arr2.join("\r\n");
    };
}

Answer 6

我认为应该这样做:

var arr = ['contains,comma', 3.14, 'contains"quote', "more'quotes"]
var item, i;
var line = [];

for (i = 0; i < arr.length; ++i) {
    item = arr[i];
    if (item.indexOf && (item.indexOf(',') !== -1 || item.indexOf('"') !== -1)) {
        item = '"' + item.replace(/"/g, '""') + '"';
    }
    line.push(item);
}

document.getElementById('out').innerHTML = line.join(',');

小提琴

基本上它所做的就是检查字符串是否包含逗号或引号.如果确实如此,那么它会将所有报价加倍,并在两端加上引号.然后它用逗号连接每个部分.

Answer 7

使用内置Array.toString方法

var arr = ['one', 'two', 'three'];
arr.toString();  // 'one,two,three'

Array.toString()上的MDN

Answer 8

有很多方法可以将数组转换为逗号分隔的列表

1.使用array＃join

从MDN

join（）方法将数组（或类似数组的对象）的所有元素连接到字符串中。

代码

var arr = ["this","is","a","comma","separated","list"];
arr = arr.join(",");

片段

var arr = ["this","is","a","comma","separated","list"];
arr = arr.join(",");

2.使用array＃toString

从MDN

toString（）方法返回表示指定数组及其元素的字符串。

代码

var arr = ["this","is","a","comma","separated","list"];
arr = arr.toString();

片段

var arr = ["this", "is", "a", "comma", "separated", "list"];
arr = arr.join(",");
console.log(arr);

3.在数组前添加[] +或在数组后添加+ []

在[] +或+ []将其转换成字符串

证明

([]+[] === [].toString())

将输出true

var arr = ["this","is","a","comma","separated","list"];
arr = arr.toString();

var arr = ["this","is","a","comma","separated","list"];
arr = []+arr;

片段

var arr = ["this", "is", "a", "comma", "separated", "list"];
arr = arr.toString();
console.log(arr);

也

var arr = ["this","is","a","comma","separated","list"];
arr = arr+[];

([]+[] === [].toString())

Answer 9

如果您需要在最后两项之间使用“和”而不是“，”，则可以执行以下操作：

function arrayToList(array){
  return array
    .join(", ")
    .replace(/, ((?:.(?!, ))+)$/, ' and $1');
}