Delete rows with null values from a csv file in c#

Question

How can I delete a row which contains null values from a comma separated csv file in c# ?

Example:
|      FirstName      |     LastName     |      Email    |    Address   |
|---------------------|------------------|---------------|--------------|
|          lmn        |         lmn      |[email protected]    |DemoAddress   |
|          xy         |         xy       |[email protected]      |DemoAddress   |
|          demo       |         demo     |               |              |
|          demo2      |         demo2    |[email protected]      |DemoAddress   |

    

Outcome:
|      FirstName      |     LastName     |      Email    |    Address   |
|---------------------|------------------|---------------|--------------|
|          lmn        |         lmn      |[email protected]    |DemoAddress   |
|          xy         |         xy       |[email protected]      |DemoAddress   |
|          demo2      |         demo2    |[email protected]      |DemoAddress   |

I tried the following code but doesn't work as expected

        private string filterCSV(string strFilePath) 
        { 
            var columnIndex = 3;
            var line = File.ReadAllLines(strFilePath);
            var n = line.Where(x => x[columnIndex].Equals(""));
            string result = string.Join("\r", not.ToArray());

            return result;

        }

There are many different ways. The simplest one is to read the file, process it, write to a temporary file, swap and delete the old file. — freakish
– freakish, Commented Aug 19, 2022 at 7:32
There's really no way to just remove part of a file. It's basically a case of read it in, do what you need to, then write it out. The options are in the details. If it's a small file then the simplest option is to read all the lines into a collection, remove the ones you don't want, then write the collection back out to the file. If it's a large file, you're better reading the lines one by one and writing the ones you want to keep out to a new file, then moving the new file to overwrite the original file. — John
– John, Commented Aug 19, 2022 at 7:41
I have edited the question with the code I tried.. would really appreciate if anyone can help out — Chirag Atha
– Chirag Atha, Commented Aug 21, 2022 at 13:38

Chirag Atha · Accepted Answer · 2022-08-23 05:38:08Z

1

Adding answer for future reference

private void RemoveBlanks(string datapath)
        {
            List<CSV> records;
            using (var reader = new StreamReader(datapath))
            using (var csv = new CsvReader(reader, CultureInfo.InvariantCulture))
            {
                records = csv.GetRecords<CSV>().ToList();
                for(int i = 0; i < records.Count;++i)
                {
                    if (records[i].Email== "" && records[i].Address == "")
                    {
                        
                        records.RemoveAt(i);
                    }
                }

            }
            using (var writer = new StreamWriter(datapath))
            using (var csv = new CsvWriter(writer, CultureInfo.InvariantCulture))
            {
                csv.WriteRecords(records);
            }           
        }

edited Aug 23, 2022 at 5:38

answered Aug 23, 2022 at 5:35

Chirag Atha

113 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Delete rows with null values from a csv file in c#

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related