If function

This code should work if you are writing a calculated column that has the row context to make sense of it.

However, for a measure, it doesn't automatically know which row you're referring to when you write "test[item]", so you need to use an aggregation like MAX or SELECTEDVALUE like this:

IF ( SELECTEDVALUE ( test[item] ) = "A", 1, 0 )

1. I'd probably write that like this:

IF ( SELECTEDVALUE ( test[item] ) IN { "A", "B", "C" }, 1, 0 )

2. Font face cannot be conditionally formatted like font color and background color can be. Not yet anyway.

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