I sometimes use braces to isolate a block of code to avoid using by mistake a variable later. For example, when I put several SqlCommand
s in the same method, I frequently copy-paste blocks of code, ending by mixing the names and executing twice some commands. Adding braces helps to avoid this situation, because using a wrong SqlCommand
in a wrong place will result in an error. Here's an illustration:
Collection<string> existingCategories = new Collection<string>();
// Here a beginning of a block
{
SqlCommand getCategories = new SqlCommand("select Title from Movie.Category where SourceId = @sourceId", sqlConnection, sqlTransaction);
getCategories.Parameters.AddWithValue("@sourceId", sourceId);
using (SqlDataReader categoriesReader = getCategories.ExecuteReader(System.Data.CommandBehavior.SingleResult))
{
while (categoriesReader.Read())
{
existingCategories.Add(categoriesReader["Title"].ToString());
}
}
}
if (!existingCategories.Contains(newCategory))
{
SqlCommand addCategory = new SqlCommand("insert into Movie.Category (SourceId, Title) values (@sourceId, @title)", sqlConnection, sqlTransaction);
// Now try to make a mistake and write/copy-paste getCategories instead of addCategory. It will not compile.
addCategory.Parameters.AddWithValue("@sourceId", sourceId);
addCategory.Parameters.AddWithValue("@title", newCategory);
addCategory.ExecuteNonQuery();
}
Now, StyleCop displays a warning every time a block follows an empty line. On the other hand, not putting an empty line would make the code much harder to understand.
// Something like:
Collection<string> existingCategories = new Collection<string>();
{
// Code here
}
// can be understood as (is it easy to notice that semicolon is missing?):
Collection<string> existingCategories = new Collection<string>()
{
// Code here
}
So,
Is there something wrong in using braces to create blocks of code just for variable scope purposes?
If it's all right, how to make it more readable without violating StyleCop rules?
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