ADF Switch Expression Adding Unexpected Characters to FileName

Question

The pipeline involves a file landing in an SFTP Blob container, which is decrypted by a .Net application. After the decryption and movement to a designated folder, a pipeline is triggered to load the file into a SQL table.

A Get Metadata activity successfully retrieves the FileName ChildItems into a variable activity. The "FileNameVariable" extracts the "FileName" and passes it to a Switch expression as follows:

• @activity('Get Metadata1').output.childItems[0].name

The Switch expression uses "Contains" logic:

• @{if(contains(variables('FileNameVariable'), 'ExampleCase1'),'ExampleCase1', 'Default')}

During debugging, the filename in "FileNameVariable" correctly holds the full filename. However, the expression in the switch evaluates the "FileNameVariable" with unexpected characters like "ExampleCase1 /n/n:", which causes the switch to revert to the default case instead of matching properly.

What could be the reason for the addition of the /n/n or /t/n characters to the end of the filename? Any insights would be appreciated.

Answer 1

Try to trim the filename to remove any leading or trailing whitespace or newline characters before using it in the switch expression :

   @{if(contains(trim(variables('FileNameVariable')), 'ExampleCase1'), 'ExampleCase1', 'Default')}

Or use the toString() function to make sure that the variable is treated as a string.

   @{if(contains(toString(variables('FileNameVariable')), 'ExampleCase1'), 'ExampleCase1', 'Default')}