C# ExcelWorksheet 单元格值读取错误

Question

I am parsing a csv file using C# and ExcelWorksheet. I have a cell that contains an integer. 3020191002155959391100

When I parse the cell using

var value = sheet.Cells[rowNumber, columnNumber.Column].Value; value is 3.0201910021559592E+21

when I parse the cell using sheet.Cells[rowNumber, columnNumber.Column].Text;the value is 3020191002155960000000

how do I prevent the rounding off?

Answer 1

The maximum value of an int in C# is

int.MaxValue: 2,147,483,647

Source: https://www.dotnetperls.com/int-maxvalue

Therefore your number is too big to be read as an int .

However, upon reading your comments it appears that you're using the Excel reader to read a CSV file, which is the wrong tool for the job. Use a CSV parser such as CSVHelper ( https://joshclose.github.io/CsvHelper/ ) which will make your life easy.

Here's an example of how to read such long numbers as string using CSVHelper .

First I'll create a class to match your CSV file. I created a dummy CSV file that looks like the following. Simply, three long numbers in a row.

3020191002155959391100,3020191002155959391101,3020191002155959391102

Now I create a class like so:

class CSVRecord
{
    public string Data1 { get; set; }
    public string Data2 { get; set; }
    public string Data3 { get; set; }
}

Then you can read all the records in one go. Note the csv.Configuration settings, depending on the complexity of the file you read you'll have to change those. I advice you to read the documentation and examples on the link provided.

var file = @"data.csv";
var records = new List<CSVRecord>();

using (var reader = new StreamReader(file))
{
    using (var csv = new CsvReader(reader))
    {
        csv.Configuration.HasHeaderRecord = false;
        records = csv.GetRecords<CSVRecord>().ToList();
    }
}

Answer 2

I needed to set the specific column types to string, before processing each cell.

columnDataTypes.Add(eDataTypes.String);