Exporting double value to CSV

Question

I am trying to export double values to a CSV file as follows

double[] arr = new double[] { 0.0000074, 0.00000123, 0.0000001254 };
using (StreamWriter writer = new StreamWriter(@"D:\Test.csv"))
{
    foreach (double item in arr)
    {
        writer.WriteLine(item);
    }
};

The output when CSV is opened in Excel/Notepad is the same and is as follows

7.40E-06
1.23E-06
1.25E-07

Expecting the output to be same as the input in the CSV file. Looking forward to any kind of input/suggestions. Thanks.

Answer 1

You could specify the format of the double string by putting floating-point format like "F9":

double[] arr = new double[] { 0.0000074, 0.00000123, 0.0000001254 };
using (StreamWriter writer = new StreamWriter(@"D:\Test.csv"))
{
    foreach (double item in arr)
    {
        writer.WriteLine(item.ToString("F9")); //note the F9
    }
};

9 is the amount of number you want to keep after decimal separator (.). You could specify the number as you want (for instance F10, F11, etc...)

Answer 2

Save them as string instead for double;

using (StreamWriter writer = new StreamWriter(@"D:\Test.csv"))
{
    foreach (double item in arr)
    {
        writer.WriteLine(item.ToString("#.#########");
    }
};

For Formatting you can use any of the following:

"C", "E", "e", "F", "G", "N", "P", 
"R", "#,000.000", "0.###E-000",
"000,000,000,000.00###"