本文整理汇总了VB.NET中System.Data.Constraint类的典型用法代码示例。如果您正苦于以下问题：VB.NET Constraint类的具体用法？VB.NET Constraint怎么用？VB.NET Constraint使用的例子？那么, 这里精选的类代码示例或许可以为您提供帮助。
在下文中一共展示了Constraint类的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的VB.NET代码示例。
示例1: GetConstraints
Private Sub GetConstraints(dataTable As DataTable)
Console.WriteLine()
' Print the table's name.
Console.WriteLine("TableName: " & dataTable.TableName)
' Iterate through the collection and print
' each name and type value.
Dim constraint As Constraint
For Each constraint In dataTable.Constraints
Console.WriteLine("Constraint Name: " _
& constraint.ConstraintName)
Console.WriteLine("Type: " _
& constraint.GetType().ToString())
' If the constraint is a UniqueConstraint,
' print its properties using a function below.
If TypeOf constraint Is UniqueConstraint Then
PrintUniqueConstraintProperties(constraint)
End If
' If the constraint is a ForeignKeyConstraint,
' print its properties using a function below.
If TypeOf constraint Is ForeignKeyConstraint Then
PrintForeigKeyConstraintProperties(constraint)
End If
Next constraint
End Sub
Private Sub PrintUniqueConstraintProperties( _
constraint As Constraint)
Dim uniqueConstraint As UniqueConstraint
uniqueConstraint = CType(constraint, UniqueConstraint)
' Get the Columns as an array.
Dim columnArray() As DataColumn
columnArray = uniqueConstraint.Columns
' Print each column's name.
Dim i As Integer
For i = 0 To columnArray.Length - 1
Console.WriteLine("Column Name: " _
& columnArray(i).ColumnName)
Next i
End Sub
Private Sub PrintForeigKeyConstraintProperties( _
constraint As Constraint)
Dim fkConstraint As ForeignKeyConstraint
fkConstraint = CType(constraint, ForeignKeyConstraint)
' Get the Columns as an array.
Dim columnArray() As DataColumn
columnArray = fkConstraint.Columns
' Print each column's name.
Dim i As Integer
For i = 0 To columnArray.Length - 1
Console.WriteLine("Column Name: " _
& columnArray(i).ColumnName)
Next i
Console.WriteLine()
' Get the related columns and print each columns name.
columnArray = fkConstraint.RelatedColumns
For i = 0 To columnArray.Length - 1
Console.WriteLine("Related Column Name: " _
& columnArray(i).ColumnName)
Next i
Console.WriteLine()
End Sub