c# - 在 InvocatioExpression 中插入新方法调用

Question

我正在使用提供程序编写一个 Visual Studio 代码修复程序，它将在此类语句中插入 AsEnumerable 调用:

model.clients.Take(10).Select(c => new Client(c));

我能够检测到此类语句，但在 Select 方法之前插入 AsEnumerable 时遇到问题。这是我尝试过的:

        var expressionSyntax = SyntaxFactory.ParseExpression(".AsEnumerable()");
        var memberAccessExpressionSyntax = invocationExpr.Expression as MemberAccessExpressionSyntax;

        var root = await document.GetSyntaxRootAsync(cancellationToken);

        var newRoot = root.InsertNodesAfter(memberAccessExpressionSyntax.Expression, new[] {expressionSyntax});

        return document.WithSyntaxRoot(newRoot);

但我明白了

"System.InvalidOperationException: The item specified is not the element of a list."

查看堆栈跟踪:https://gist.github.com/anonymous/02c41f232829163b25ae

调用 InsertNodesAfter 方法的正确方法是什么？

Answer 1

这就是我解决这个问题的方法:

var memberAccessExpressionSyntax = invocationExpr.Expression as MemberAccessExpressionSyntax;

var root = await document.GetSyntaxRootAsync(cancellationToken);

var accessExpression = SyntaxFactory.MemberAccessExpression(SyntaxKind.SimpleMemberAccessExpression, memberAccessExpressionSyntax.Expression, SyntaxFactory.IdentifierName("AsEnumerable"));

var invocationExpression = SyntaxFactory.InvocationExpression(accessExpression);
var enumerableMemberAccessExpression = memberAccessExpressionSyntax.WithExpression(invocationExpression);

root = root.ReplaceNode(invocationExpr, invocationExpr.WithExpression(enumerableMemberAccessExpression));