获取方法的所有引用

var syntaxRoot = await document.GetSyntaxRootAsync();

var semanticModel = await document.GetSemanticModelAsync();
var sampleMethodInvocation = syntaxRoot
    .DescendantNodes()
    .OfType<InvocationExpressionSyntax>()
    .First();

var sampleMethodSymbol = semanticModel.GetSymbolInfo(sampleMethodInvocation).Symbol;
var referencesToSampleMethod = await SymbolFinder.FindReferencesAsync(sampleMethodSymbol, document.Project.Solution);