KeyValuePair.cs

using System.Text;

namespace System.Collections.Generic
{
    [Serializable]
    [__DynamicallyInvokable]
    public struct KeyValuePair<TKey, TValue>
    {
        private TKey key;

        private TValue value;

        [__DynamicallyInvokable]
        public TKey Key
        {
            [__DynamicallyInvokable]
            get
            {
                return key;
            }
        }

        [__DynamicallyInvokable]
        public TValue Value
        {
            [__DynamicallyInvokable]
            get
            {
                return value;
            }
        }

        [__DynamicallyInvokable]
        public KeyValuePair(TKey key, TValue value)
        {
            this.key = key;
            this.value = value;
        }

        [__DynamicallyInvokable]
        public override string ToString()
        {
            StringBuilder stringBuilder = StringBuilderCache.Acquire();
            stringBuilder.Append('[');
            if (Key != null)
            {
                stringBuilder.Append(Key.ToString());
            }
            stringBuilder.Append(", ");
            if (Value != null)
            {
                stringBuilder.Append(Value.ToString());
            }
            stringBuilder.Append(']');
            return StringBuilderCache.GetStringAndRelease(stringBuilder);
        }
    }
}