如何找到List<>中的最后一个元素？ [英] How can I find the last element in a List<>?

问题描述

以下是我的代码的摘录：

The following is an extract from my code:

public class AllIntegerIDs 
{
    public AllIntegerIDs() 
    {            
        m_MessageID = 0;
        m_MessageType = 0;
        m_ClassID = 0;
        m_CategoryID = 0;
        m_MessageText = null;
    }
    
    ~AllIntegerIDs()
    {
    }

    public void SetIntegerValues (int messageID, int messagetype,
        int classID, int categoryID)
    {
        this.m_MessageID = messageID;
        this.m_MessageType = messagetype;
        this.m_ClassID = classID;
        this.m_CategoryID = categoryID;
    }
    
    public string m_MessageText;
    public int m_MessageID;
    public int m_MessageType;
    public int m_ClassID;
    public int m_CategoryID;
}

我正在尝试在我的 main（）中使用以下内容函数代码：

I am trying to use the following in my main() function code:

List<AllIntegerIDs> integerList = new List<AllIntegerIDs>();

/* some code here that is ised for following assignments*/
{
   integerList.Add(new AllIntegerIDs());
   index++;
   integerList[index].m_MessageID = (int)IntegerIDsSubstring[IntOffset];
   integerList[index].m_MessageType = (int)IntegerIDsSubstring[IntOffset + 1];
   integerList[index].m_ClassID = (int)IntegerIDsSubstring[IntOffset + 2];
   integerList[index].m_CategoryID = (int)IntegerIDsSubstring[IntOffset + 3];
   integerList[index].m_MessageText = MessageTextSubstring;
}

问题在这里：我正在尝试使用for循环打印列表中的所有元素：

Problem is here: I am trying to print all elements in my List using a for loop:

for (int cnt3 = 0 ; cnt3 <= integerList.FindLastIndex ; cnt3++) //<----PROBLEM HERE
{
   Console.WriteLine("{0}\t{1}\t{2}\t{3}\t{4}\n", integerList[cnt3].m_MessageID,integerList[cnt3].m_MessageType,integerList[cnt3].m_ClassID,integerList[cnt3].m_CategoryID, integerList[cnt3].m_MessageText);
}

我想找到最后一个元素，以便将cnt3等同于我的for循环并打印出所有内容列表中的条目。列表中的每个元素都是 AllIntegerIDs 类的对象，如上面的代码示例所述。如何在列表中找到最后一个有效条目？

I want to find the last element so that I equate cnt3 in my for loop and print out all entries in the List. Each element in the list is an object of the class AllIntegerIDs as mentioned above in the code sample. How do I find the last valid entry in the List?

我应该使用类似 integerList.Find（integerList []。m_MessageText == null; ？

如果我使用它，它将需要一个从0到最大值的索引，这意味着我将不得不使用另一个我不打算使用的for循环

If I use that it will need an index that will range from 0 to whatever maximum. Means I will have to use another for loop which I do not intend to use. Is there a shorter/better way?

推荐答案

如果只想访问列表中的最后一项，则可以执行

If you just want to access the last item in the list you can do

if(integerList.Count>0)
{
   var item = integerList[integerList.Count - 1];
}

要获取列表中的项目总数，可以使用 Count 属性

to get the total number of items in the list you can use the Count property

var itemCount = integerList.Count;

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