How to convert float or double to string

Question

i have a variable such this

double a=123456789012345678901234567890.1234567890123456;

i want to convert a(above variable) to string value in

console.writeline();

when i write

a.ToString();

i see the result as

1.23456789012346E+29

but only i want to have a varable such below.

string s="123456789012345678901234567890.1234567890123456";

how can i make s from a?

use a big decimal class? https://www.nuget.org/packages/BigDecimal/ — Mitch Wheat, Jan 11 '19 at 12:24
Maybe using a [custom/built-in format](https://learn.microsoft.com/en-us/dotnet/api/system.double.tostring?view=netframework-4.7.2#System_Double_ToString_System_String_) will help? — Uwe Keim, Jan 11 '19 at 12:24
duplicate of ? https://stackoverflow.com/questions/4523741/arbitrary-precision-decimals-in-c-sharp/4524254#4524254 — Mitch Wheat, Jan 11 '19 at 12:25
`double` has 64-bit length only; that's why *precision loss* is inevitable. — Dmitry Bychenko, Jan 11 '19 at 12:31
refer this format and simply apply https://learn.microsoft.com/en-us/dotnet/api/system.double.tostring?redirectedfrom=MSDN&view=netframework-4.7.2#System_Double_ToString_System_String_ — Hitesh Anshani, Jan 11 '19 at 13:50

score 1 · Answer 1 · answered Jan 11 '19 at 12:29

You can't, since double doesn't have such a high precision you can save the entire number into the double. (To see what part is actually saved, try Console.WriteLine(a.ToString("n9"));)

You have to use another data type that does support such high precision numbers, for example BigDecimal.

How to convert float or double to string

1 Answers1