Compartilhar via

Turn off constraints while filling a dataset

  • Artigo

Applies to: yesVisual Studio noVisual Studio for Mac

Note

This article applies to Visual Studio 2017. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here

If a dataset contains constraints (such as foreign-key constraints), they can raise errors related to the order of operations that are performed against the dataset. For example, loading child records before loading related parent records can violate a constraint and cause an error. As soon as you load a child record, the constraint checks for the related parent record and raises an error.

If there were no mechanism to allow temporary constraint suspension, an error would be raised every time you tried to load a record into the child table. Another way to suspend all constraints in a dataset is with the BeginEdit, and EndEdit properties.

Note

Validation events (for example, ColumnChanging and RowChanging) will not be raised when constraints are turned off.

To suspend update constraints programmatically

  • The following example shows how to temporarily turn off constraint checking in a dataset:

    dataSet1.EnforceConstraints = false;
// Perform some operations on the dataset
dataSet1.EnforceConstraints = true;

    DataSet1.EnforceConstraints = False
' Perform some operations on the dataset
DataSet1.EnforceConstraints = True

To suspend update constraints using the Dataset Designer

  1. Open your dataset in the Dataset Designer. For more information, see Walkthrough: Creating a dataset in the Dataset Designer.

  2. In the Properties window, set the EnforceConstraints property to false.

See also