How to check for Empty when extracting SdtBlock

Question

I have the following code which works perfect if the document contains the content control which has tag name same as the variable value.

mainPart.Document.Body.Descendants<sdtblock>().Where(r => r.SdtProperties.GetFirstChild<tag>().Val == myVar).Single();</tag></sdtblock>

But this line throws a Sequence is Empty exception if the document does not contain any content control which has the Tag/Title of the variable value.

Can you please tell me how to build some resiliency in the code?

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MSDNStudent Knows not much!

Answer 1

Hi,

You can use Try Catch statement to prevent getting a exception if the document doesn't contain any Content Controls or there is a content control whose tag name matches what you specify, see:

       SdtBlock block = null;
            try
            {
                block = body.Descendants<SdtBlock>().Where(r => r.SdtProperties.GetFirstChild<Tag>().Val == var).First();
            }
            catch
            {
            }
            if (block != null)
            {
                block.SdtProperties.GetFirstChild<Tag>().Val = "MyCustomTag";
            }

i hope this helps.

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Calvin Gao[MSFT]
MSDN Community Support | Feedback to us

Answer 2

I am currently using FirstOrDefault method. this is causing the error to stop

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MSDNStudent Knows not much!