The latest articles on DEV Community by Vinícius Mamoré (@vmamore). https://dev.to/vmamore https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F302759%2Ff7b5aee2-297b-4358-86bd-a824ed272b67.jpg https://dev.to/vmamore en Vinícius Mamoré Fri, 10 Jul 2020 22:47:34 +0000 https://dev.to/vmamore/como-definir-contratos-para-importacao-de-arquivos-texto-com-c-34cp https://dev.to/vmamore/como-definir-contratos-para-importacao-de-arquivos-texto-com-c-34cp <p>Olá! Tudo bem?</p> <p>Recentemente necessitei de uma funcionalidade onde lia arquivos texto e criava objetos. Estava fazendo um trabalho bem repetitivo e minhas classes que instanciavam os objetos, precisavam saber em qual posição do array deveria buscar para setar nas propriedades:</p> <p><a href="https://res.cloudinary.com/practicaldev/image/fetch/s--huYMBoD1--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/pm2s8nvg69j1iwy9zamf.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--huYMBoD1--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/pm2s8nvg69j1iwy9zamf.PNG" alt="Alt Text"></a><br> ^{<em>Meu arquivo texto.</em>}</p> <p>Dessa forma:<br> <a href="https://res.cloudinary.com/practicaldev/image/fetch/s--Klhe0oKu--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/vc7z3v47nl4we2bmyn90.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--Klhe0oKu--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/vc7z3v47nl4we2bmyn90.PNG" alt="Alt Text"></a></p> <p>Assim, pensei na possibilidade de minhas classes DTOs definirem nas propriedades quais posições do arquivo os valores delas estava. Criei um atributo para setar nas propriedades e passar o index que o valor dela está no array:</p> <p><a href="https://res.cloudinary.com/practicaldev/image/fetch/s--NR4vglA9--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/7l3p2lgeak4bdn2sintz.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--NR4vglA9--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/7l3p2lgeak4bdn2sintz.PNG" alt="Alt Text"></a></p> <p>E defini os atributos nas propriedades:</p> <p><a href="https://res.cloudinary.com/practicaldev/image/fetch/s--qh4pVWgr--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/ri4ia0oxbw0eslmjj20z.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--qh4pVWgr--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/ri4ia0oxbw0eslmjj20z.PNG" alt="Alt Text"></a></p> <p>Agora que minha classe já sabe em qual posição da linha do arquivo o valor dela está definido, eu preciso setar o valor com base na posição dela. Criei uma classe abstrata que no construtor, receberia o array da linha lida e setaria os valores nas propriedades:</p> <p><a href="https://res.cloudinary.com/practicaldev/image/fetch/s--8YzPqEDD--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/24dnwgxown3a2n73ikqz.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--8YzPqEDD--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/24dnwgxown3a2n73ikqz.PNG" alt="Alt Text"></a></p> <p>Por fim, nossa classe DTO, ficaria dessa forma e nosso método que o instancia, mais enxuto e sem a necessidade de saber quais propriedades setar:</p> <p><a href="https://res.cloudinary.com/practicaldev/image/fetch/s--CfffzXRF--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/w86gouoykqudv8w0owq7.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--CfffzXRF--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/w86gouoykqudv8w0owq7.PNG" alt="Alt Text"></a></p> <p><a href="https://res.cloudinary.com/practicaldev/image/fetch/s--BAue80ET--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/ylbpxdxb103djelwf3at.PNG" class="article-body-image-wrapper"><img src="https://res.cloudinary.com/practicaldev/image/fetch/s--BAue80ET--/c_limit%2Cf_auto%2Cfl_progressive%2Cq_auto%2Cw_880/https://dev-to-uploads.s3.amazonaws.com/i/ylbpxdxb103djelwf3at.PNG" alt="Alt Text"></a></p> <p>Acredito que tenha perdido um pouco de performance por conta do uso de Reflection, farei um post comparando com o BenchmarkDotNet, entretanto conseguimos generalizar o comportamento necessário.</p> <p>É isto! Você vê alguma forma que posso melhorar meu código ou outra abordagem? Comenta aí!</p> <p>Até mais!</p> csharp dotnet braziliandevs