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  1. using System;
  2. using System.Linq.Expressions;
  3. using System.Reflection;
  4.  
  5. public class Test
  6. {
  7.         private object Foo { get; }
  8.         private object Bar { get; }
  9.  
  10.         static void MyMethod(params Expression<Func<Test,object>>[] fields) {
  11.             foreach (var fieldExpr in fields) {
  12.                 var finder = new Finder("Foo");
  13.                 finder.Visit(fieldExpr);
  14.                 if (finder.IsFound) {
  15.                     Console.WriteLine("Expression {0} reference 'Foo'", fieldExpr);
  16.                 } else {
  17.                     Console.WriteLine("Expression {0} does not reference 'Foo'", fieldExpr);
  18.                 }
  19.             }
  20.         }
  21.  
  22.         static void Main(string[] args) {
  23.             MyMethod(e => e.Foo, e => e.Bar, e => e.Bar != null ? e.Foo : e.Bar);
  24.         }
  25. }
  26.  
  27.  
  28.     internal class Finder : ExpressionVisitor {
  29.         private readonly string toFind;
  30.  
  31.         public Finder(string toFind) {
  32.             this.toFind = toFind;
  33.         }
  34.  
  35.         public bool IsFound { get; private set; }
  36.  
  37.         protected override Expression VisitMember(MemberExpression node) {
  38.             IsFound |= node.Member.MemberType == MemberTypes.Property && node.Member.Name == toFind;
  39.             return base.VisitMember(node);
  40.         }
  41.     }
  42.  
Success #stdin #stdout 0.02s 132672KB
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stdin
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Standard input is empty
stdout
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Expression e => e.Foo reference 'Foo'
Expression e => e.Bar does not reference 'Foo'
Expression e => IIF((e.Bar != null), e.Foo, e.Bar) reference 'Foo'
https://ideone.com/wpiQDr
language:
C# (gmcs 5.20.1)
created:
7 years ago
visibility:
public

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