参数异常“已添加具有相同密钥的项目”

我不断收到以下代码的错误：

Dictionary<string, string> rct3Features = new Dictionary<string, string>();
Dictionary<string, string> rct4Features = new Dictionary<string, string>();

foreach (string line in rct3Lines) 
{
    string[] items = line.Split(new String[] { " " }, 2, StringSplitOptions.None);

    rct3Features.Add(items[0], items[1]);

    ////To print out the dictionary (to see if it works)
    //foreach (KeyValuePair<string, string> item in rct3Features)
    //{
    //    Console.WriteLine(item.Key + " " + item.Value);
    //}

}

该错误引发ArgumentException说，

“已添加具有相同密钥的项目。”

经过几次谷歌搜索后我不确定如何解决这个问题。

稍后在代码中我需要访问字典以进行比较函数：

Compare4To3(rct4Features, rct3Features);

public static void Compare4To3(Dictionary<string, string> dictionaryOne, Dictionary<string, string> dictionaryTwo)
{
    //foreach (string item in dictionaryOne)
    //{

    //To print out the dictionary (to see if it works)
    foreach (KeyValuePair<string, string> item in dictionaryOne)
    {
        Console.WriteLine(item.Key + " " + item.Value);
    }

        //if (dictionaryTwo.ContainsKey(dictionaryOne.Keys)
        //{
        //    Console.Write("True");
        //}
        //else
        //{
        //    Console.Write("False");
        //}
    //}
}

此功能尚未完成，但我正在尝试解决此异常。我可以通过哪些方法来修复此异常错误，并保留对字典的访问权限以便与此函数一起使用？谢谢

这个错误是不言自明的。字典键是唯一的，您不能拥有多个相同的键。要解决此问题，您应该像这样修改代码：

Dictionary<string, string> rct3Features = new Dictionary<string, string>();
Dictionary<string, string> rct4Features = new Dictionary<string, string>();

foreach (string line in rct3Lines) 
{
    string[] items = line.Split(new String[] { " " }, 2, StringSplitOptions.None);

    if (!rct3Features.ContainsKey(items[0]))
    {
        rct3Features.Add(items[0], items[1]);
    }

    ////To print out the dictionary (to see if it works)
    //foreach (KeyValuePair<string, string> item in rct3Features)
    //{
    //    Console.WriteLine(item.Key + " " + item.Value);
    //}
}

这个简单的if语句确保您仅在 Key (items[0]) 尚未存在。