StringSwitchInstruction.cs

Go to the documentation of this file.

using System.Collections.Generic;
using System.Runtime.CompilerServices;
 
namespace System.Linq.Expressions.Interpreter;
 
internal sealed class StringSwitchInstruction : Instruction
{
    private readonly Dictionary<string, int> _cases;
 
    private readonly StrongBox<int> _nullCase;
 
    public override string InstructionName => "StringSwitch";
 
    public override int ConsumedStack => 1;
 
    internal StringSwitchInstruction(Dictionary<string, int> cases, StrongBox<int> nullCase)
    {
        _cases = cases;
        _nullCase = nullCase;
    }
 
    public override int Run(InterpretedFrame frame)
    {
        object obj = frame.Pop();
        if (obj == null)
        {
            return _nullCase.Value;
        }
        if (!_cases.TryGetValue((string)obj, out var value))
        {
            return 1;
        }
        return value;
    }
}