c# - Roslyn:获取数组值

Question

我尝试使用 Roslyn 获取数组值。例如，如果我有这样的 C# 代码:

int[] arrInt = {10, 20, 30, 40, 50};

那我怎么才能得到arrInt[0]是10，arrInt[1]是20，等等。

Answer 1

我鼓励你 check the documentation , FAQ and samples ，尤其是语法和语义分析部分。

解决方法如下:

static void Main(string[] args)
{
    string code = "int[] arrInt = {10, 20, 30, 40, 50};";

    //Parse Syntax tree
    var tree = Roslyn.Compilers.CSharp.SyntaxTree.ParseText(code);

    //Locate the arrInt identifier in the Syntax tree
    var declarator = tree.GetRoot().DescendantNodesAndSelf().Where(t => t.Kind == Roslyn.Compilers.CSharp.SyntaxKind.VariableDeclarator
        && ((Roslyn.Compilers.CSharp.VariableDeclaratorSyntax)t).Identifier.ValueText == "arrInt").First() as Roslyn.Compilers.CSharp.VariableDeclaratorSyntax;

    var index = 1;
    var expression = GetExpressionAtInitializer(declarator, index);

    Console.WriteLine(expression);

    //Examine 'expression' for more information on value at the second index            
}

private static Roslyn.Compilers.CSharp.ExpressionSyntax GetExpressionAtInitializer(Roslyn.Compilers.CSharp.VariableDeclaratorSyntax declarator, int index)
{
    var initializerExpression = declarator.Initializer.Value as Roslyn.Compilers.CSharp.InitializerExpressionSyntax;
    var expression = initializerExpression.Expressions[index];
    return expression;
}

可以使用VS的quick watch window来查看语法树的层级。

如果您对代码应用一些语义分析，您可能能够获得有关代码中符号的更有意义的信息。