Automatically Validating Property Values

On the Validation tab of the Property Definition Properties dialog, you can define the criteria that the values of a specific property should meet. For example, with validation you can ensure that the property value contains a required number of characters. In this way, you can verify that the customer phone number or invoice number is added correctly on the metadata card. You can also validate that, for instance, the value can be accepted in relation to other properties or that the value is not empty.

Validation is specified by using variables, generic features of VBScript, and M-Files API. The following M-Files variables can be used for validating property values: PropertyDef, PropertyValue, ObjVer, DisplayID, Vault, CurrentUserID, CurrentUserSessionInfo, VaultSharedVariables, SavepointVariables, TransactionCache, MFScriptCancel, GetExtensionObject, MasterTransactionID, CurrentTransactionID, ParentTransactionID. For more information about the variables, refer to Available VBScript Variables.

By default, validation is considered successful. Invalid values are thus detected using conditional statements and should any of the conditions specified in the validation be met, then an error should be raised, prompting the user to correct the invalid value (for instance, Err.Raise MFScriptCancel, "The property must have a value of at least 10 characters.").

Complete the following steps to add value validation for a property:

  1. Open M-Files Admin.
  2. In the left-side tree view, expand a connection to M-Files server.
  3. Expand Document Vaults.
  4. Expand a vault.
  5. Expand Metadata Structure (Flat View).
  6. Click Property Definitions.
  7. Either:
    • In the Property Definitions list, right-click the property, the values of which you want to be automatically validated, and select Properties from the context menu.
    • In the task area, click New Property Definition to create a new property definition with automatic value validation.
    Result:The Property Definition Properties dialog is opened.
  8. Go to the Validation tab.
    Result:The Validation tab is opened.
  9. Select the Validation with VBScript option and click the Edit Code... button.
    Result:The Edit VBScript Code window is opened.
  10. In the Edit VBScript Code window, type in the VBScript code for validating the values of this property.
    Example:If the values of this property must have at least 10 characters, you could use the following code:
    Option Explicit
    Dim propertyName, value
    propertyName = PropertyDef.Name
    value = PropertyValue.GetValueAsUnlocalizedText
    If Len(value) < 10 Then
        Err.Raise MFScriptCancel, "The property """ & propertyName & """ must have a value of at least 10 characters."
    End If
    Note: The M-Files API documentation is available online: M-Files API. For more information about using VBScript in M-Files, see the How do I write VBScript code for M-Files purposes? tutorial.
  11. Close the Edit VBScript Code window and then click Apply in the Property Definition Properties dialog to save your changes.
The values entered for the selected property are now automatically validated. When entering a value for the property on the metadata card, the value is validated and if it does not meet the criteria specified, the action specified in the validation script is executed (such as displaying an error message).