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Boolean.TryParse Method

Tries to convert the specified string representation of a logical value to its Boolean equivalent. A return value indicates whether the conversion succeeded or failed.

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

public static bool TryParse(
	string value,
	out bool result
)

Parameters

value
Type: System.String

A string containing the value to convert.

result
Type: System.Boolean

When this method returns, if the conversion succeeded, contains true if value is equal to Boolean.TrueString or false if value is equal to FalseString. If the conversion failed, contains false. The conversion fails if value is null or is not equal to the value of either the TrueString or FalseString field.

Return Value

Type: System.Boolean
true if value was converted successfully; otherwise, false.

The TryParse method is like the Parse method, except the TryParse method does not throw an exception if the conversion fails.

The value parameter can be preceded or followed by white space. The comparison is ordinal and case-insensitive.

The following example calls the TryParse 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 Main()
   {
      string[] values = { null, String.Empty, "True", "False", 
                          "true", "false", "    true    ", "0", 
                          "1", "-1", "string" };
      foreach (var value in values) {
         bool flag;
         if (Boolean.TryParse(value, out flag))
            Console.WriteLine("'{0}' --> {1}", value, flag);
         else
            Console.WriteLine("Unable to parse '{0}'.", 
                              value == null ? "<null>" : value);
      }                                     
   }
}
// The example displays the following output: 
//       Unable to parse '<null>'. 
//       Unable to parse ''. 
//       'True' --> True 
//       'False' --> False 
//       'true' --> True 
//       'false' --> False 
//       '    true    ' --> True 
//       Unable to parse '0'. 
//       Unable to parse '1'. 
//       Unable to parse '-1'. 
//       Unable to parse 'string'.

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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