Double.ToString Method
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Converts the numeric value of this instance to its equivalent string representation.
Assembly: mscorlib (in mscorlib.dll)
The return value can be PositiveInfinitySymbol, NegativeInfinitySymbol, NaNSymbol, or a string of the form:
[sign]integral-digits[.[fractional-digits]][e[sign]exponential-digits]
Optional elements are framed in square brackets ([ and ]). Elements containing the term "digits" consist of a series of numeric characters ranging from 0 to 9. The elements listed in the following table are supported:
Element | Description |
|---|---|
sign | A negative sign or positive sign symbol. |
integral-digits | A series of digits specifying the integral part of the number. Integral-digits can be absent if there are fractional-digits. |
'.' | A culture-specific decimal point symbol. |
fractional-digits | A series of digits specifying the fractional part of the number. |
'e' | A lowercase character 'e', indicating exponential (scientific) notation. |
exponential-digits | A series of digits specifying an exponent. |
Some examples of the return value are "100", "-123,456,789", "123.45e+6", "500", "3.1416", "600", "-0.123", and "-Infinity".
This version of the ToString method implicitly uses the general numeric format specifier ("G") and the NumberFormatInfo for the current culture.
The .NET Framework provides extensive formatting support, which is described in greater detail in the following formatting topics:
For more information about numeric format specifiers, see Standard Numeric Format Strings and Custom Numeric Format Strings.
For more information about formatting, see Formatting Types.
Version Notes
Windows Phone
ToString does not return the correct string containing comma delimiters between group digits when a custom format is used.The following example uses the default Double.ToString() method to display the string representations of a number of Double values.
double number; number = 1.6E20; // Displays 1.6E+20. outputBlock.Text += number.ToString() + "\n"; number = 1.6E2; // Displays 160. outputBlock.Text += number.ToString() + "\n"; number = -3.541; // Displays -3.541. outputBlock.Text += number.ToString() + "\n"; number = -1502345222199E-07; // Displays -150234.5222199. outputBlock.Text += number.ToString() + "\n"; number = -15023452221990199574E-09; // Displays -15023452221.9902. outputBlock.Text += number.ToString() + "\n"; number = .60344; // Displays 0.60344. outputBlock.Text += number.ToString() + "\n"; number = .000000001; // Displays 1E-09. outputBlock.Text += number.ToString() + "\n";
The following example illustrates the use of ToString.
bool done = false; string inp; do { outputBlock.Text += "Enter a real number: "; inp = Console.ReadLine(); try { d = Double.Parse(inp); outputBlock.Text += String.Format("You entered {0}.", d.ToString()) + "\n"; done = true; } catch (FormatException) { outputBlock.Text += "You did not enter a number." + "\n"; } catch (Exception e) { outputBlock.Text += String.Format("An exception occurred while parsing your response: {0}", e.ToString()) + "\n"; } } while (!done);