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c#regexwebformsuser-controls

Regex parsing "^[-\wÀ-ÿ\'\.\-\&\s]+$" - [x-y] range in reverse order

Older C# ASP.Net Web Form app with.Net Framework 4.6.2.

I have a regexp validator in an ascx user control:

<asp:RegularExpressionValidator ID="REV_RecordId" runat="server" 
        ControlToValidate="uxRecordID" 
        ValidationGroup="TheValidationGroup" 
        Display="Dynamic" 
        ForeColor="Red"
        ErrorMessage="Please enter a valid ID" 
        SetFocusOnError="True" 
        ValidationExpression="^[-\wÀ-ÿ\'\.\-\&\s]+$" />

but when this control is loaded with

UserControl ctrl = (UserControl)LoadControl("path to user control");

I get the exception:

Inner Exception 1:
ArgumentException: parsing "^[-\wÀ-ÿ'.-&\s]+$" - [x-y] range in reverse order.

but any regex validator says "^[-\wÀ-ÿ'.-&\s]+$" is valid, the higher character component saying "matches a single character in the range between À (index 192) and ÿ (index 255) (case sensitive)".

So why would this fail with showing even stranger character interpretations?

Solution

  • is there an UTF16-encoded version of À and ÿ?

    That is not the question you should be asking. The question you should be asking is "in which encoding have I saved the file containing my <asp:RegularExpressionValidator>, and in which encoding should I have saved it instead?"

    Your regex is seeing a different expression than the one you have written in the file, which is because the file is not being read in the same encoding you saved it in.