Determine the number of objects in a collection using the collection's Count property:
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' Set a variable equal to the number of Splits in C1TrueDBGrid1. variable = Me.C1TrueDBGrid1.Splits.Count |
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// Set a variable equal to the number of Splits in C1TrueDBGrid1. variable = this.c1TrueDBGrid1.Splits.Count; |
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Iterate through all objects in a collection using the Count property as in the following example, which prints the Caption string of each C1DataColumn object in a grid:
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For n = 0 To Me.C1TrueDBGrid1.Columns.Count - 1
Debug.WriteLine(Me.C1TrueDBGrid1.Columns(n).Caption)
Next n
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for (n = 0; n < this.c1TrueDBGrid1.Columns.Count; n++)
{
Console.WriteLine(this.c1TrueDBGrid1.Columns[n].Caption);
}
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The Count property is also useful for appending and removing columns:
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' Determine how many columns there are.
Dim NumCols As Integer
NumCols = Me.C1TrueDBGrid1.Columns.Count
' Append a column to the end of the Columns collection.
Dim C As C1TrueDBGrid.C1DataColumn = New C1TrueDBGrid.C1DataColumn()
Me.C1TrueDBGrid1.Columns.Insert(NumCols, C)
' Make the new column visible, since columns created at run timeare invisible by default.
Me.C1TrueDBGrid1.Splits(0).DisplayColumns(C).Visible = True
' The following loop removes all columns from the grid.
While Me.C1TrueDBGrid1.Columns.Count
Me.C1TrueDBGrid1.Columns.RemoveAt(0)
End While
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// Determine how many columns there are.
int NumCols;
NumCols = this.c1TrueDBGrid1.Columns.Count;
// Append a column to the end of the Columns collection.
C1TrueDBGrid.C1DataColumn C = new C1TrueDBGrid.C1DataColumn();
this.c1TrueDBGrid1.Columns.Insert(NumCols, C);
// Make the new column visible, since columns created at run time are invisible by default.
this.c1TrueDBGrid1.Splits[0].DisplayColumns[C].Visible = true;
// The following loop removes all columns from the grid.
while ( this.c1TrueDBGrid1.Columns.Count > 0 )
{
this.c1TrueDBGrid1.Columns.RemoveAt(0);
}
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An efficient For Each...Next statement that can be used iterate through the objects in a collection without using the Count property:
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Dim C As C1TrueDBGrid.C1DataColumn
For Each C In Me.C1TrueDBGrid1.Columns
Debug.WriteLine(C.Caption)
Next S
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C1TrueDBGrid.C1DataColumn c;
foreach (c In this.c1TrueDBGrid1.Columns)
{
Console.WriteLine(c);
}
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In fact, using the For Each...Next statement is the easiest way to iterate through the objects in a collection.