If you are trying to use the HTML Helper RenderPartial and you received the following error:

CS1502: The best overloaded method match for 'System.IO.TextWriter.Write(char)' has some invalid arguments error

do worry, you are not alone.  When I was trying to upgrade DimeCasts.Net to Preview 5 I was getting this error.  What was really odd, was that the exception and stack trace did not really make sense.  It was not till I read Brad Wilson's blog did I realize what the issue was.

Take a look at the following code:

<%= Html.RenderPartial("somecontrol.ascx",  SomeDataEntity )  %>

What you will notice is that the code above has an = sign in the markup.  I left this because I converted this code from Html.RenderUserControl which needed the '=' as it returned a string.  Since RenderPartial is void method you do NOT NEED the '='.

Try removing the '=' sign and see if your issue goes away.

The correct code would be:

<% Html.RenderPartial("somecontrol.ascx",  SomeDataEntity )  %>

Hope this helps someone else.

Till next time,

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