roslyn Analyze source code with Roslyn Get the type of 'var'

Example

To get the actual type for a variable declared using var, call GetSymbolInfo() on the SemanticModel. You can open an existing solution using MSBuildWorkspace, then enumerate its projects and their documents. Use a document to obtain its SyntaxRoot and SemanticModel, then look for VariableDeclarations and retrieve the symbols for the Type of a declared variable like this:

var workspace = MSBuildWorkspace.Create();
var solution = workspace.OpenSolutionAsync("c:\\path\\to\\solution.sln").Result;

foreach (var document in solution.Projects.SelectMany(project => project.Documents))
{
    var rootNode = document.GetSyntaxRootAsync().Result;
    var semanticModel = document.GetSemanticModelAsync().Result;

    var variableDeclarations = rootNode
            .DescendantNodes()
            .OfType<LocalDeclarationStatementSyntax>();
    foreach (var varDeclaration in variableDeclarations)
    {
        var symbolInfo = semanticModel.GetSymbolInfo(varDeclaration.Declaration.Type);
        var typeSymbol = symbolInfo.Symbol; // the type symbol for the variable..
    }
}