ErrorProvider::GetError Method (Control^)

 

Returns the current error description string for the specified control.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public:
String^ GetError(
	Control^ control
)

Parameters

control
Type: System.Windows.Forms::Control^

The item to get the error description string for.

Return Value

Type: System::String^

The error description string for the specified control.

Exception Condition
ArgumentNullException

control is null.

The following code example uses the GetError method to check for an error before opening a file dialog box. To run this example, paste the following code into a form containing a TextBox named TextBox1, an OpenFileDialog named OpenFileDialog1, a button named Button1, and an ErrorProvider named ErrorProvider1. Ensure all events are associated with their event handlers.

private:
   void TextBox1_Validating( Object^ sender,
      System::ComponentModel::CancelEventArgs^ e )
   {
      // If nothing is entered,
      // an ArgumentException is caught; if an invalid directory is entered, 
      // a DirectoryNotFoundException is caught. An appropriate error message 
      // is displayed in either case.
      try
      {
         System::IO::DirectoryInfo^ directory = gcnew System::IO::DirectoryInfo( TextBox1->Text );
         directory->GetFiles();
         ErrorProvider1->SetError( TextBox1, "" );
      }
      catch ( System::ArgumentException^ ) 
      {
         ErrorProvider1->SetError( TextBox1, "Please enter a directory" );
      }
      catch ( System::IO::DirectoryNotFoundException^ ) 
      {
         ErrorProvider1->SetError( TextBox1, "The directory does not exist."
         "Try again with a different directory." );
      }
   }

   // This method handles the LostFocus event for TextBox1 by setting the 
   // dialog's InitialDirectory property to the text in TextBox1.
   void TextBox1_LostFocus( Object^ sender, System::EventArgs^ e )
   {
      OpenFileDialog1->InitialDirectory = TextBox1->Text;
   }

   // This method demonstrates using the ErrorProvider.GetError method 
   // to check for an error before opening the dialog box.
   void Button1_Click( System::Object^ sender, System::EventArgs^ e )
   {
      //If there is no error, then open the dialog box.
      if ( ErrorProvider1->GetError( TextBox1 )->Equals( "" ) )
      {
         ::DialogResult dialogResult = OpenFileDialog1->ShowDialog();
      }
   }

.NET Framework
Available since 1.1
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