set a value to the attribute at run time

Question

I have a namespace that contains some classes, one of the classes I'm working on contains properties, where each proprty has an attribute associated with it, as the follwing

namespace Local.Business
{
    [DynamoDBTable("myTableName")]     
    public class Business
    {
        [DynamoDBHashKey("PK")] 
        public string MunId {get; set;}

        [DynamoDBRangeKey("SK")]
        public string Id {get; set;}

        [DynamoDBProperty("Dba")] 
        public string Dba {get; set;} 
    }
}

the string "myTableName" need to be determined at runtime(by calling a function or reading it from other class's property) How can I achieve that, please?

It's a bad idea to try and edit the data stored in attributes, but if you really need to then you'll need to use reflection. — Sean, Mar 04 '20 at 12:22
have a look on this so question [C# How to set attributes values using reflection](https://stackoverflow.com/questions/2160476/how-to-set-attributes-values-using-reflection) — rekcul, Mar 04 '20 at 12:23
@Sean that just doesn't work: https://gist.github.com/mgravell/08b20ed8fd7c4da714028a15eb1893d0 — Marc Gravell, Mar 04 '20 at 12:32

score 0 · Answer 1 · answered Mar 04 '20 at 12:25

What you are trying to do is inherently flawed. You kinda can ish change attributes sort of, sometimes, but there's a good chance that whatever is consuming the attributes won't see the change, which makes it entirely pointless.

Basically: you need to find another way of reconfiguring DynamoDB at runtime. This isn't it.

For the "kinda can ish":

you can materialize attributes, and if they're mutable, change the copies you have; but when other code materializes the attributes, they'll get different unrelated versions, which will not have any changes you have made
there is an API that supports this concept (System.ComponentModel), but: most attribute consumers do not use that API - it is mostly just UI binding tools (think PropertyGrid, DataGridView, etc) that would take any notice of it - because they are expecting to work with things like DataTable that require a different approach to metadata and reflection

score 0 · Answer 2 · answered Mar 04 '20 at 19:32

0

Set the table name value to empty string in the class file:

[DynamoDBTable("")]

During runtime, use the overloaded functions on DynamoDBMapper to pass DynamoDBMapperConfig configured with TableNameOverride

answered Mar 04 '20 at 19:32

Parag Kutarekar

975
11
10

score 0 · Answer 3 · answered Mar 08 '20 at 09:45

Actually I deleted the table property and I gave the table name in the query

 dynamoDBOperationConfig = new DynamoDBOperationConfig();
 dynamoDBOperationConfig.OverrideTableName = "tableName";
 string munId = "1";
 var search = dynamoDBcontext.QueryAsync<Business>(munId, dynamoDBOperationConfig);

and It works fine, thank you all guys for helping

set a value to the attribute at run time

3 Answers3