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Stopwatch.StartNew Method

Initializes a new Stopwatch instance, sets the elapsed time property to zero, and starts measuring elapsed time.

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

'Declaration
Public Shared Function StartNew As Stopwatch

Return Value

Type: System.Diagnostics.Stopwatch
A Stopwatch that has just begun measuring elapsed time.

This method is equivalent to calling the Stopwatch constructor and then calling Start on the new instance.

The following example uses the Stopwatch class to measure the performance of four different implementations for parsing an integer from a string. This code example is part of a larger example provided for the Stopwatch class.


Dim ticksThisTime As Long = 0
Dim inputNum As Integer
Dim timePerParse As Stopwatch

Select Case operation
   Case 0
      ' Parse a valid integer using
      ' a try-catch statement.
      ' Start a new stopwatch timer.
      timePerParse = Stopwatch.StartNew()

      Try
         inputNum = Int32.Parse("0")
      Catch e As FormatException
         inputNum = 0
      End Try

      ' Stop the timer, and save the
      ' elapsed ticks for the operation.
      timePerParse.Stop()
      ticksThisTime = timePerParse.ElapsedTicks
   Case 1
      ' Parse a valid integer using
      ' the TryParse statement.
      ' Start a new stopwatch timer.
      timePerParse = Stopwatch.StartNew()

      If Not Int32.TryParse("0", inputNum) Then
         inputNum = 0
      End If

      ' Stop the timer, and save the
      ' elapsed ticks for the operation.
      timePerParse.Stop()
      ticksThisTime = timePerParse.ElapsedTicks
   Case 2
      ' Parse an invalid value using
      ' a try-catch statement.
      ' Start a new stopwatch timer.
      timePerParse = Stopwatch.StartNew()

      Try
         inputNum = Int32.Parse("a")
      Catch e As FormatException
         inputNum = 0
      End Try

      ' Stop the timer, and save the
      ' elapsed ticks for the operation.
      timePerParse.Stop()
      ticksThisTime = timePerParse.ElapsedTicks
   Case 3
      ' Parse an invalid value using
      ' the TryParse statement.
      ' Start a new stopwatch timer.
      timePerParse = Stopwatch.StartNew()

      If Not Int32.TryParse("a", inputNum) Then
         inputNum = 0
      End If

      ' Stop the timer, and save the
      ' elapsed ticks for the operation.
      timePerParse.Stop()
      ticksThisTime = timePerParse.ElapsedTicks

   Case Else
End Select


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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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