Error parsing AppSettings value with a query string

Question

In my AppSettings in web.config, I have something like this:

<appSettings>
    <add key="ExternalSystemUrl" value="http://example.com/page.aspx?id={0}&action=eat&object=bacon" />
</appSettings>

However, it seems that when an ampersand (&) is included in an AppSettings value, ASP.NET throws the following error:

An error occurred while parsing EntityName

Why does this happen, and how can I include URLs like this in App.config?

Stephen Ostermiller · Accepted Answer · 2022-07-05 07:35:57Z

50

Replace & with & (escape it):

<add
    key="ExternalSystemUrl"
    value="http://example.com/page.aspx?id={0}&amp;action=eat&amp;object=bacon" />

That's the common requirement for any valid XML file.

See Where can I get a list of the XML document escape characters?

edited Jul 5, 2022 at 7:35

Stephen Ostermiller♦

25.8k18 gold badges96 silver badges117 bronze badges

answered Jun 10, 2011 at 12:36

abatishchev

101k88 gold badges304 silver badges443 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Wicked Coder · Accepted Answer · 2011-06-10 12:36:57Z

6

You can Try using & instead.

answered Jun 10, 2011 at 12:36

Wicked Coder

1,1186 silver badges8 bronze badges

Comments

Chris White · Accepted Answer · 2011-06-10 12:37:05Z

4

In XML an ampersand tells the parser "the data immediately following this ampersand is an entity which needs to be translated." If the data immediately following is not a valid XML entity, then you get this error. If possible, use & for your ampersand within the XML.

answered Jun 10, 2011 at 12:37

Chris White

1,0736 silver badges11 bronze badges

Collectives™ on Stack Overflow

Error parsing AppSettings value with a query string

3 Answers 3

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related