JS浏览器扩展到控制台日志字

Question

我正在构建一个浏览器扩展程序，最终将其转变为翻译程序，但出于当前目的，我只希望我的扩展程序可以记录在页面上单击的单词。我正在使用香草JS：

using System;
using System.Diagnostics;
using System.Runtime.CompilerServices;

namespace InformalTests
{

    class Program
    {
        const int n = 100_000_000;

        static unsafe void Main(string[] args)
        {
            var watch = Stopwatch.StartNew();
            for (int i =0; i < n; i++)
            {
                ThisMethodDoes_NOT_InitializeStackAllocatedMemory();
            }
            watch.Stop();
            Console.WriteLine($"NOT INITIALIZED elapsed time {watch.Elapsed}");

            watch.Restart();
            for (int i = 0; i < n; i++)
            {
                ThisMethodInitializeStackAllocatedMemory();
            }
            watch.Stop();
            Console.WriteLine($"INITIALIZED Elapsed time {watch.Elapsed}");
        }


        private static unsafe string ThisMethodDoes_NOT_InitializeStackAllocatedMemory()
        {
            // avoid declaring other local vars, or doing work with stackalloc
            // to prevent the .locals init cil flag , see: https://github.com/dotnet/coreclr/issues/1279
            char* pointer = stackalloc char[256];
            return CreateString(pointer, 256);
        }

        private static unsafe string ThisMethodInitializeStackAllocatedMemory()
        {
            //Declaring a variable other than the stackallocated, causes
            //compiler to emit .locals int cil flag, so it's slower
            int i = 256;
            char* pointer = stackalloc char[256];
            return CreateString(pointer, i);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        private static unsafe string CreateString(char* pointer, int length)
        {
            return "";
        }
    }
}

如果我删除了window.addEventListener('mouseup', checkWord); function checkWord() { console.log('the word is') let word = window.getSelection().toString(); console.log(word); } 方法，程序将把整个对象返回到控制台。但是，使用.toString()方法时，控制台日志会给我一个空的回报。我应该使用其他方法提取点击的实际单词吗？