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DataSet.Clear Method

Clears the DataSet of any data by removing all rows in all tables.

[Visual Basic]
Public Sub Clear()
[C#]
public void Clear();
[C++]
public: void Clear();
[JScript]
public function Clear();

Remarks

If the DataSet is bound to an XmlDataDocument, calling DataSet.Clear or DataTable.Clear raises the NotSupportedException. To avoid this situation, traverse each table, removing each row one at a time.

Example

[Visual Basic, C#, C++] The following example clears the DataSet of all rows in all tables.

[Visual Basic] 
Private Sub ClearDataSet(ByVal myDataSet As DataSet)
   ' To test, print the number rows in each table.
  Dim t As DataTable
  For Each t In myDataSet.Tables
      Console.WriteLine(t.TableName & "Rows.Count = " & t.Rows.Count.ToString())
   Next
   ' Clear all rows of each table.
   myDataSet.Clear()
   ' Print the number of rows again.
  For Each t In myDataSet.Tables
      Console.WriteLine(t.TableName & "Rows.Count = " & t.Rows.Count.ToString())
   Next 
End Sub

[C#] 
private void ClearDataSet(DataSet myDataSet){
   // To test, print the number rows in each table.
   foreach(DataTable t in myDataSet.Tables){
      Console.WriteLine(t.TableName + "Rows.Count = " + t.Rows.Count.ToString());
   }
   // Clear all rows of each table.
   myDataSet.Clear();
   // Print the number of rows again.
   foreach(DataTable t in myDataSet.Tables){
      Console.WriteLine(t.TableName + "Rows.Count = "  + t.Rows.Count.ToString());
   }
}

[C++] 
private:
 void ClearDataSet(DataSet* myDataSet){
    // To test, print the number rows in each table.
    System::Collections::IEnumerator* myEnum = myDataSet->Tables->GetEnumerator();
    while (myEnum->MoveNext())
    {
       DataTable* t = __try_cast<DataTable*>(myEnum->Current);
       Console::WriteLine(S"{0}Rows->Count = {1}", t->TableName, __box(t->Rows->Count));
    }
    // Clear all rows of each table.
    myDataSet->Clear();
    // Print the number of rows again.
    System::Collections::IEnumerator* myEnum1 = myDataSet->Tables->GetEnumerator();
    while (myEnum1->MoveNext())
    {
       DataTable* t = __try_cast<DataTable*>(myEnum1->Current);
       Console::WriteLine(S"{0}Rows->Count = {1}", t->TableName, __box(t->Rows->Count));
    }
 }

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework

See Also

DataSet Class | DataSet Members | System.Data Namespace

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