c# - LINQ Join with multiple or conditions -

my question similar question linq join multiple conditions in on clause , other similar question either talk having properties map respective conditions or writing query without join

from t1 in projects t2 in tasks.where(x => t1.projectid == x.projectid && x.completed == true)                 .defaultifempty() select new { t1.projectname, t2.taskname } 

suppose if go first way of writing i.e.

on new { t1.projectid, secondproperty = true } equals     new { t2.projectid, secondproperty = t2.completed } j1 

that gets converted , (&&). want or (||) in join form (2nd way of writing).

thanks in advance.

if want perform join projectid , have || on secondproperty must join 1 field , add where clause:

from t1 in projects join t2 in tasks on t1.projectid equals t2.projectid t1.secondproperty || t1.secondproperty == t2.completed select new { t1, t2 } 

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