PostgreSQL in a String for Visual Studio 2019

This is a separate PostgreSQL in a String extension that targets only Visual Studio 2019. Extension for Visual Studio 2022 can be found on the here.

PostgreSQL in a String is a Visual Studio extension that adds highlighting for PostgreSQL syntax in C# string literals.

Applies only to C# .cs files.

Supports regular quoted strings "", verbatim strings @"", interpolated strings $"" and interpolated verbatim strings $@"". Does not support C#11 raw string literals yet (I plan on tackling this after .NET 8 comes out).

Supports parametrized queries. Parameters prefixed with an @ are colorized in golden.

Correctly handles string escape sequences.

PostgreSQL in a String uses an ANTLR 4 lexer to tokenize PostgreSQL syntax.

How to enable and disable highlighting

The extension does not automatically detect string literals with PostgreSQL syntax. The syntax highlighting must be explicitly enabled for a single string literal, a code region or whole project.

Note: Rule configuration inside XML documentation comments (starting with /// or /**) are ignored.

Inline rule configuration

Highlighting can be enabled inline by prefixing a string literal with a comment containing strpsql text or PostgreSqlInAString (if you prefer to be more explicit). Note that only block comments can be used as the comment must be directly adjacent to the beginning of string literal.

string sql = /*strpsql*/@"SELECT COUNT(*) FROM order;";

When the string literal is inside an enabled region, its highlighting can be disabled inline by prefixing it with a comment containing strpsql-ignore text or PostgreSqlInAString-ignore for a longer version.

string text = /*strpsql-ignore*/"Just a regular string, no SQL here";

Region rule configuration

Enable or disable highlighting in code regions with rule configuration comments. A region configuration will override highlighting of every string literal after it, except for those prefixed with inline rule configuration, until the next region configuration or end of file.

Short version:

• // strpsql-on
• // strpsql-off

Longer version:

• /* PostgreSqlInAString-enable */
• /* PostgreSqlInAString-disable */

The rule parts can be mixed, e.g. /*strpsql-enable*/ will work too.

Project configuration

To have the highlighting enabled by default for an entire project, add the following section in the .csproj file (or merge it with existing ProjectExtensions element).

<ProjectExtensions>
  <PostgreSqlInAString>
    <Enabled>true</Enabled>
  </PostgreSqlInAString>
</ProjectExtensions>

This may be useful when you have a separate data access project where most of the strings are database queries.

Explanations

Rule configuration comments can contain explanations similar to what ESLint rule configuration comments allow.

To add an explanation to the configuration, add two dashes after the rule name (separated by some whitespace) and place your explanation after the dashes.

/* strpsql-off -- This is HTML */
string str = "<select>" +
             "   <option>Apple</option>" +
             "   <option>Orange</option>" +
             "</select>";
/* strpsql-on -- That was HTML */

string sql = /* PostgreSqlInAString -- hey, 
              *    this is an explanation
              *    that spans multiple lines.
              */@"TRUNCATE address, order_product, order, product RESTART IDENTITY;";

Highlighting configuration

The default highlight colors were selected for VS dark theme but they can be customized in Tools > Options > Environment > Fonts and Colors > String SQL * [ - escape character]

The default colors except for parameter color are a mix of 50% default string color and 50% default SQL token color. This means that the highlighted text will have an orange tint, which is by design, to not overwhelm you when combined with other C# syntax as it is still just a string.

Possible further improvements

• Support for raw string literals
• Highlighting of PL/pgSQL in a string in a string
• Autocompletion
• Light-mode-friendly color palette and auto-switching between palettes when mode is changed
• Basic error recognition (typos, unsupported keyword order, etc.) by using an ANTLR parser
• Support for more language syntaxes in string literals: T-SQL, HTML, etc.