即使密钥存在，TryGetValue返回false [英] TryGetValue returns false even though the key exists

问题描述

我有一个称为UnicodeMap的模型类，用于表示十六进制unicode值及其辅音和Amharic字符的值。

I have a model class called UnicodeMap that I use to represent the hexadecimal unicode value and its consonants and values for Amharic characters.

public sealed class UnicodeMap
    {

        public string Letter;

        public string Consonant;

        public string Vowel;


    }

我已将映射存储为CSV，在运行时中读取以填充字典。

I have stored the mapping in CSV and read in runtime to populate a dictionary.

以下是读取并填充字典的代码摘录：

Here is the excerpt of the code that reads and populates the dictionary:

private Dictionary<string, UnicodeMap> _unicodeMap;

void ReadMap()
{
            var engine = new FileHelperAsyncEngine<UnicodeMap>();

            using (engine.BeginReadFile(MapFile))
            {
                foreach (var record in engine)
                {

                      _unicodeMap.Add(record.Letter, record);
                }
            }
 }

当我尝试获取一个使用TryGetValue从字典中获得的值，它总是返回false：

When I try to get a value from the dictionary using TryGetValue, it always returns false:

 public void Translate(string text)
    {
            var words = text.Split(' ', '.');
            foreach (var word in words)
            {
                var chr = Char.Parse(word);
                var unicodeStr = @"\u" + ((int) chr).ToString("X4");
                UnicodeMap map;
                if (_unicodeMap.TryGetValue(unicodeStr, out map)) //returns false
                {
                    _animator.SetTrigger(map.Consonant);
                    _animator.SetTrigger(map.Vowel);
                };
            }
    }

例如，当字符串为时ሀ ， unicodeStr 变量的值为 \u1200。而且我在字典中有一个值为 \u1200的字符串作为键。但是， TryGetValue 似乎无法在字典中找到键。

For example, when the string is "ሀ", the value of the unicodeStr variable is "\u1200". And I have a string with the value "\u1200" as a key in the dictionary. However, TryGetValue cannot seem to find the key in the dictionary.

如何解决此问题？可能的原因是什么？

How can I solve this issue? What is the possible cause?

编辑：：添加了调试器的gif，以查看_ unicodeMap 的值。字典

Added a gif of the debugger looking at the values of _unicodeMap dictionary

推荐答案

在gif中很难看到，但是在字典键中的文本后面似乎有一个空格，因此您实际上是在比较 \u1200和 \u1200。

It's a little hard to see in the gif, but it appears you have a trailing space after the text in the dictionary keys, so you are actually comparing "\u1200" and "\u1200 ".

通过对键进行 .Trim（）来固定字典的填充方式。

Fix the way you populate the dictionary by doing a .Trim() on the key.

private Dictionary<string, UnicodeMap> _unicodeMap;

void ReadMap()
{
        var engine = new FileHelperAsyncEngine<UnicodeMap>();

        using (engine.BeginReadFile(MapFile))
        {
            foreach (var record in engine)
            {

                  _unicodeMap.Add(record.Letter.Trim(), record); //Added .Trim()
            }
        }
}

或修复 FileHelperAsyncEngine ，不要在 Letter 属性中保留尾随空格。

Or fix FileHelperAsyncEngine to not leave the trailing space in the Letter property.

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