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c# - When using LINQ, what is the difference between && and multiple where clauses?

I am new to LINQ and discovered yesterday that you can have multiple where clauses such as:

var items = from object in objectList
where object.value1 < 100  
where object.value2 > 10  
select object;

Or you can write:

var items = from object in objectList
where object.value1 < 100  
   && object.value2 > 10  
select object;

What is the difference between the two?

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The first one will be translated into:

objectList.Where(o => o.value1 < 100).Where(o=> o.value2 > 10)

while the second one will be translated in:

objectList.Where(o => o.value1 < 100 && o.value2 > 10)

So, in the first one, you will have a first filtered sequence that is filtered again (first sequence contains all the objects with value < 100, the second one containing all the objects with value > 10 from the first sequence), in while the second one you will do the same comparisons in the same labda expression. This is valid fro Linq to objects, for other providers it depends how the expression is translated.


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