Dapper : Custom Map column to nested object

Question

Dapper : Custom Map column to nested object

c# dapper orm

Question

I want to map a column value to nested object.

for example in my database table i have:

Users
(
 varchar UserName,
 varchar Password,
 binary  Permitions
)

in my code i have:

User{string UserName, string Password, Permition Permitions: {...}}

I want to do something like

db.Query<User>("Select UserName, Password, Permisions PermitionsFromTable
from Users WHERE UserName=@User AND Password =@Password", new { user, 
password
}, user =>
 {
 user.Permitions = new Permition();
 user.Permitions.LoadPermitions("PermitionsFromTable");
 return user ;
});

it's possible?

Alejandro Mora

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juharr · Accepted Answer · 4/11/2017 12:30:34 AM

There's an overload of Query that lets you specify more than one type to map to and a result type and you can tell it the column to split on, then you can combine the types. So, something like this should work for what you want.

db.Query<User, byte[], User>(
    queryString,
    new { user, password },
    splitOn: "PermisionsFromTable",
    (user, perm) =>
    {
        user.Permitions = new Permition();
        user.Permitions.LoadPermitions(perm);
        return user;
    });

Dapper : Custom Map column to nested object

Question

Fastest Dapper Plus Extensions

Accepted Answer

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Expression Evaluator