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Asked: 2026-06-17T21:57:50+00:00

I am new to the Entity Framework and while I have the basics down,

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I am new to the Entity Framework and while I have the basics down, I am stumbling over a specific syntax that I do not understand. The code works, but it is a bit of a “black box” to me and I fee a bit hampered by not understanding it.

I have a local private variable declared in my class as thus:

private clientexperienceEntities ceContext;

Farther in my code I instantiate it thus:

ceContext = new clientexperienceEntities();

This next line is the portion I am having difficulty with:

var client = ceContext.clients.First(a => a.ID == _ID);

Specifically the parameters to the First method, what exactly does a => a.ID == _ID mean? I know it is telling the context to find the first matching record based on the primary key value contained in the _ID value. But I don’t understand where the ‘a’ comes from, or whatever other name I want to use, ‘b’ or ‘cat’.

Is this syntax part of Linq? I am not even sure what exactly to search for to understand it.

As I said the statement works, and I can the manipulate the entity returned, but I just don’t fully understand that parameter construct.

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1 Answer

  1. Editorial Team

    what exactly does a => a.ID == _ID mean?

    It is a labmda expression and acts as a filter.

    This is identical do – more clear for someone who did not read the documentation:

    clients.Where(x => x.ID == _ID).First ();

    The expression compares the field ID (x.ID) on the object X (which is every object in the query) against the value of _ID (which has to be a local variable, naming would indicate so).

    It is a filter. Get me first item where the FIeld ID is the value of the variable ID.

    Reading up on Lambda Expressions is needed here – you will not get far without understanding them.

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