I'm using KnockoutJS in my MVc Project to load a csv file & provide a simple validation for import mechanism

The workflow is as follows:

• User selects a CSV file (sample provided).
• User clicks a button (weehoo...).
• Client-side code takes the CSV, parses it, and loads it into KnockoutJS array. All is working Perfect i can upload the file but the problem that my Code Load The Empty line in csv files, I dont want that the user remove the empty lines manual before importing the file

this is an example of csv Lines :

Account_id,External_id,Amount,Transaction_Date,Office_date,Bank,Receipt_nbr,Type,statement,receipt,

0559394,,5,6/20/2017,7/7/2017,Cash,1729002903597,PNL,172900290,3597,

0099952,,19,6/20/2017,7/7/2017,Cash,1729002903653,PNL,172900290,3653,

,,,,,,,,,,

,,,,,,,,,,

,,,,,,,,,,

Here my code used to Upload file :

$('#lnkUpload').click(function () {
    var FileToRead = document.getElementById('UserFile');
    if (FileToRead.files.length > 0) {
        var reader = new FileReader();
        // assign function to the OnLoad event of the FileReader  
        // non synchronous event, therefore assign to other method  
        reader.onload = Load_CSVData;
        // call the reader to capture the file  
        reader.readAsText(FileToRead.files.item(0));
    }
    self.userModel.removeAll();

});

 function Load_CSVData(e) {
    self.userModel.removeAll();


    CSVLines = e.target.result.split(/\r\n|\n/);
    $CSVLines = CSVLines.slice(1);
    $.each($CSVLines, function (i, item) {

        var element = item.split(","); // builds an array from ma delimited items  
        var LAccount_id = (element[0] == undefined) ? "" : element[0].trim();
        var LExternal_id = (element[1] == undefined) ? "" : element[1].trim();
        var LAmount = (element[2] == undefined) ? "" : element[2].trim();
        var LTransaction_date = (element[3] == undefined) ? "" : element[3].trim();
        var LOffice_date = (element[4] == undefined) ? "" : element[4].trim();
        var LBank = (element[5] == undefined) ? "" : element[5].trim();
        var LReceipt_nbr = (element[6] == undefined) ? "" : element[6].trim();
        var LType = (element[7] == undefined) ? "" : element[7].trim();
        var Lstatement = (element[8] == undefined) ? "" : element[8].trim();
        var Lreceipt = (element[9] == undefined) ? "" : element[9].trim();






        self.userModel.push(new userModel()
            .Account_id(LAccount_id)
            .External_id(LExternal_id)
            .Amount(LAmount)
            .Transaction_date(LTransaction_date)
            .Office_date(LOffice_date)
            .Bank(LBank)
            .Receipt_nbr(LReceipt_nbr)
            .Type(LType)
            .statement(Lstatement)
            .receipt(Lreceipt))

    });

}

how can i update the code to Ignore and skip over empty Lines or treat them as the end of the input file or any other suggestion

I'm using KnockoutJS in my MVc Project to load a csv file & provide a simple validation for import mechanism

The workflow is as follows:

• User selects a CSV file (sample provided).
• User clicks a button (weehoo...).
• Client-side code takes the CSV, parses it, and loads it into KnockoutJS array. All is working Perfect i can upload the file but the problem that my Code Load The Empty line in csv files, I dont want that the user remove the empty lines manual before importing the file

this is an example of csv Lines :

Account_id,External_id,Amount,Transaction_Date,Office_date,Bank,Receipt_nbr,Type,statement,receipt,

0559394,,5,6/20/2017,7/7/2017,Cash,1729002903597,PNL,172900290,3597,

0099952,,19,6/20/2017,7/7/2017,Cash,1729002903653,PNL,172900290,3653,

,,,,,,,,,,

,,,,,,,,,,

,,,,,,,,,,

Here my code used to Upload file :

$('#lnkUpload').click(function () {
    var FileToRead = document.getElementById('UserFile');
    if (FileToRead.files.length > 0) {
        var reader = new FileReader();
        // assign function to the OnLoad event of the FileReader  
        // non synchronous event, therefore assign to other method  
        reader.onload = Load_CSVData;
        // call the reader to capture the file  
        reader.readAsText(FileToRead.files.item(0));
    }
    self.userModel.removeAll();

});

 function Load_CSVData(e) {
    self.userModel.removeAll();


    CSVLines = e.target.result.split(/\r\n|\n/);
    $CSVLines = CSVLines.slice(1);
    $.each($CSVLines, function (i, item) {

        var element = item.split(","); // builds an array from ma delimited items  
        var LAccount_id = (element[0] == undefined) ? "" : element[0].trim();
        var LExternal_id = (element[1] == undefined) ? "" : element[1].trim();
        var LAmount = (element[2] == undefined) ? "" : element[2].trim();
        var LTransaction_date = (element[3] == undefined) ? "" : element[3].trim();
        var LOffice_date = (element[4] == undefined) ? "" : element[4].trim();
        var LBank = (element[5] == undefined) ? "" : element[5].trim();
        var LReceipt_nbr = (element[6] == undefined) ? "" : element[6].trim();
        var LType = (element[7] == undefined) ? "" : element[7].trim();
        var Lstatement = (element[8] == undefined) ? "" : element[8].trim();
        var Lreceipt = (element[9] == undefined) ? "" : element[9].trim();






        self.userModel.push(new userModel()
            .Account_id(LAccount_id)
            .External_id(LExternal_id)
            .Amount(LAmount)
            .Transaction_date(LTransaction_date)
            .Office_date(LOffice_date)
            .Bank(LBank)
            .Receipt_nbr(LReceipt_nbr)
            .Type(LType)
            .statement(Lstatement)
            .receipt(Lreceipt))

    });

}

how can i update the code to Ignore and skip over empty Lines or treat them as the end of the input file or any other suggestion

• javascript
• asp-mvc
• csv
• knockout.js

• 2 if (item.length <= 10) { ... in the loop is one way to skip the ma-only or empty lines. – Alex K. Commented Jul 7, 2017 at 11:14

2 Answers 2

You can detect if the current line is a newline character.

if(item == "\n") { continue; }

EDIT:

As matt pointed out, if the whitespace is made up of spaces the above solution will not work. Simply erase any spaces to detect if the row is made up of spaces.

if(item == "\n" || item.trim().length == 0) { continue; }

This will detect a line that consists only of mas and/or white space (so will match "\n", "", ",,,,,", ", , , , ," etc. but not ",,,,1,,,,,"

if (item.match(/^[,\s]*$/)) { continue; }