Stopwatch.StartNew Método

Definição

Espaço de Nomes:
System.Diagnostics
Assemblagens:
System.dll, System.Runtime.Extensions.dll
Assemblagem:
System.dll
Assemblagem:
System.Runtime.Extensions.dll
Assemblagem:
netstandard.dll

Inicializa uma nova Stopwatch instância, define a propriedade de tempo decorrido a zero e começa a medir o tempo decorrido.

public:
 static System::Diagnostics::Stopwatch ^ StartNew();
public static System.Diagnostics.Stopwatch StartNew();
static member StartNew : unit -> System.Diagnostics.Stopwatch
Public Shared Function StartNew () As Stopwatch

Devoluções

Stopwatch

A que acabou de começar a Stopwatch medir o tempo decorrido.

Exemplos

O exemplo seguinte utiliza a Stopwatch classe para medir o desempenho de quatro implementações diferentes para analisar um inteiro a partir de uma cadeia. Este exemplo de código faz parte de um exemplo maior fornecido para a Stopwatch classe.

long ticksThisTime = 0;
int inputNum;
Stopwatch timePerParse;

switch (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 (FormatException)
        {
            inputNum = 0;
        }

        // Stop the timer, and save the
        // elapsed ticks for the operation.

        timePerParse.Stop();
        ticksThisTime = timePerParse.ElapsedTicks;
        break;
    case 1:
        // Parse a valid integer using
        // the TryParse statement.

        // Start a new stopwatch timer.
        timePerParse = Stopwatch.StartNew();

        if (!Int32.TryParse("0", out inputNum))
        {
            inputNum = 0;
        }

        // Stop the timer, and save the
        // elapsed ticks for the operation.
        timePerParse.Stop();
        ticksThisTime = timePerParse.ElapsedTicks;
        break;
    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 (FormatException)
        {
            inputNum = 0;
        }

        // Stop the timer, and save the
        // elapsed ticks for the operation.
        timePerParse.Stop();
        ticksThisTime = timePerParse.ElapsedTicks;
        break;
    case 3:
        // Parse an invalid value using
        // the TryParse statement.

        // Start a new stopwatch timer.
        timePerParse = Stopwatch.StartNew();

        if (!Int32.TryParse("a", out inputNum))
        {
            inputNum = 0;
        }

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

    default:
        break;
}

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

Observações

Este método é equivalente a chamar o Stopwatch construtor e depois chamar Start a nova instância.

Aplica-se a

Ver também