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PrinterSettings.IsValid Property

Definition

Gets a value indicating whether the PrinterName property designates a valid printer.

public bool IsValid { get; }

Property Value

true if the PrinterName property designates a valid printer; otherwise, false.

Examples

The following code example specifies the target printer by setting the PrinterName property, and if the IsValid is true, prints the document on the specified printer. The example has three prerequisites:

  • A variable named filePath has been set to the path of the file to print.

  • A method named pd_PrintPage, which handles the PrintPage event, has been defined.

  • A variable named printer has been set to the printer's name.

Use the System.Drawing, System.Drawing.Printing, and System.IO namespaces for this example.

public void Printing(string printer) {
  try {
    streamToPrint = new StreamReader (filePath);
    try {
      printFont = new Font("Arial", 10);
      PrintDocument pd = new PrintDocument(); 
      pd.PrintPage += new PrintPageEventHandler(pd_PrintPage);
      // Specify the printer to use.
      pd.PrinterSettings.PrinterName = printer;

      if (pd.PrinterSettings.IsValid) {
         pd.Print();
      } 
      else {	
         MessageBox.Show("Printer is invalid.");
      }
    } 
    finally {
      streamToPrint.Close();
    }
  } 
  catch(Exception ex) {
    MessageBox.Show(ex.Message);
  }
}

Remarks

When you get or set some properties, a valid printer is required or else an exception is raised. To avoid exceptions, use the IsValid property after setting the PrinterName to safely determine if the printer is valid.

Applies to

Продукт Версии
.NET 8 (package-provided), 9 (package-provided)
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7 (package-provided), 4.7, 4.7.1 (package-provided), 4.7.1, 4.7.2 (package-provided), 4.7.2, 4.8 (package-provided), 4.8, 4.8.1
.NET Standard 2.0 (package-provided)
Windows Desktop 3.0, 3.1, 5, 6, 7, 8, 9

See also