Tips for generating not in statements using LINQ to SQL

I used to think that the SQL statements like where id not in (1, 3, 5) or where id not in (select ID from...) are generated by LINQ to SQL ...) this condition is not very convenient. Every time I get the condition ID in an array, and then use it! When arr. Contains (C. ID) is processed like this, we suddenly find it silly today. In fact, we can directly write a sentence using LINQ, and paste an example here for future reference.

From a in tablea where! (From B in tableb where... select B. ID). Contains (A. ID)

The final translated statement is not exactly the same as not in. Instead, it uses not exists (...). However, the effect is the same, and it can meet the requirements.