javascript - 将 FileReader 的结果转换为 javascript 对象

Question

我正在使用 Javascript FileReader。我想读入 FileReader 的结果，然后将每条记录转换为 JS 对象。使用以下代码:

$("#csv").bind("change", function (event) {
            var reader = new FileReader();
            reader.onload = function (theFile) {
                try {
                    var input = $.csv.toArrays(theFile.target.result);
                    alert("CSV loaded successfully");
                    alert(input);
                }
                catch (e) {
                    alert("CSV Parse error.");
                    return;
                }
            };
            reader.readAsText(event.target.files[0]);
        });
    }

alert(input) 会将整个 csv 文件显示为字符串。我将如何从这个输入创建一个 javascript 对象数组或 JSON 字符串？换句话说，我假设我需要在第一行中读取属性集，然后每条记录都会创建一个具有该属性集的对象，并将这些对象中的每一个插入到一个数组中。

例如，来自以下字符串:

姓名、年龄、性别

约翰，20岁，男

我想创建一个对象:

{ Name: "John", Age: 20, Gender: "Male" }

提前致谢!

Answer 1

使用正则表达式

/[\w .]+(?=,?)/g

您可以按照您提到的格式从 csv 文件中提取数据(如果 .csv 文件和数据的格式不同，则需要更改 RegEx)。

Demo-RegEX

Working-Demo

示例数据。给定格式

Name,Age,Gender
John,20,Male
Cristine   ,34,FeMale
Kate Wilson,65,   FeMale
Mike,45,Male
Peter,23,Male
Katty,11,FeMale
Sandy,78,Mal

代码

var str = $('#regex_string').val();
var extractValidString = str.match(/[\w .]+(?=,?)/g)

var noOfCols = 3
//in your case it is name,age,gender so we need 3

var objFields = extractValidString.splice(0,noOfCols);
//extract columns - First Row
var arr = [];
while(extractValidString.length>0) {
    var obj = {};
    //extract remaining rows one by one
    var row = extractValidString.splice(0,noOfCols)
    for(var i=0;i<row.length;i++) {
        //make an object and put each column and set its data
        obj[objFields[i]] = row[i].trim()
    }
    //push row to an array
    arr.push(obj)
}
console.log(arr);

//output
[Object, Object, Object, Object, Object, Object, Object]
    0: Object
        Age: "20"
        Gender: "Male"
        Name: "John"
    1: Object
        Age: "34"
        Gender: "FeMale"
        Name: "Cristine"
    2: Object
        Age: "65"
        Gender: "FeMale"
        Name: "Kate Wilson"
    3: Object
        Age: "45"
        Gender: "Male"
        Name: "Mike"
    4: Object
        Age: "23"
        Gender: "Male"
        Name: "Peter"
    5: Object
        Age: "11"
        Gender: "FeMale"
        Name: "Katty"
    6: Object
        Age: "78"
        Gender: "Male"
        Name: "Sandy"
        length: 7