Boolean.Parse Method

Updated: October 2010

Converts the specified string representation of a logical value to its Boolean equivalent, or throws an exception if the string is not equivalent to the value of Boolean.TrueString or Boolean.FalseString.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public static bool Parse(
	string value


Type: System.String
A string containing the value to convert.

Return Value

Type: System.Boolean
true if value is equivalent to the value of the TrueString field; false if value is equivalent to the value of the FalseString field.


value is null.


value is not equivalent to the value of the TrueString or FalseString field.

The value parameter, optionally preceded or trailed by white space, must contain a string that is equivalent to the value of either the TrueString or FalseString field; otherwise, a FormatException is thrown. The comparison is case-insensitive.

The following example calls the Parse method to parse an array of strings. Note that the parse operation succeeds only if the string to be parsed is "True" (the value of the TrueString field) or "False" (the value of the FalseString field) in a case-insensitive comparison.

using System;

public class Example
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
      string[] values = { null, String.Empty, "True", "False", 
                          "true", "false", "    true    ", "0", 
                          "1", "-1", "string" };
      foreach (var value in values)
            bool flag = Boolean.Parse(value);
            outputBlock.Text += String.Format("'{0}' --> {1}", value, flag) + "\n";
         catch (ArgumentException)
            outputBlock.Text += "Cannot parse a null string." + "\n";
         catch (FormatException)
            outputBlock.Text += String.Format("Cannot parse '{0}'.", value) + "\n";
// The example displays the following output:
//       Cannot parse a null string.
//       Cannot parse ''.
//       'True' --> True
//       'False' --> False
//       'true' --> True
//       'false' --> False
//       '    true    ' --> True
//       Cannot parse '0'.
//       Cannot parse '1'.
//       Cannot parse '-1'.
//       Cannot parse 'string'.


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.




October 2010

Revised extensively and replaced the example.

Customer feedback.

June 2010

Corrected return value information.

Customer feedback.

Community Additions