Question

How to limit the characters in access to more than 255? for example, I want it the memo or text box to limit it to max 300 characters.

In Access 2010

Answer 1

If you want to limit a memo field in a table to no more than 300 characters, open the table in design view and add this as the field’s Validation Rule property.

Len([memo_field])<301

Substitute your field’s name for memo_field. You can also add a Validation Text property to display a more user-friendly message when the rule is violated. With no Validation Text, that rule would produce this message … which might not be very clear to a user:

*One or more values are prohibited by the validation rule ‘Len([memo_field])<301’ set for ‘YourTableName.memo_field’. Enter a value that the expression for this field can accept.*

You also mentioned a text box. If it is a text box bound to a memo field, you can validate the character length in the text box’s Before Update event. If the text box is named txtMemo_field:

Private Sub txtMemo_field_BeforeUpdate(Cancel As Integer)
    If Len(Me.txtMemo_field) > 300 Then
        MsgBox "Please limit data to maximum of 300 characters."
        Cancel = True
    End If
End Sub

After the message box, the cursor will be still located within the text box, and the user will not be allowed to move to another form field without supplying an acceptable value for txtMemo_field.