c# - 在多个数组列表中，我想重命名重复值

Question

我尝试了这段代码，因为如果我在多个 arraylist 中有重复的字符串，它会更新 1_Maths,2_Maths

例如在 multiplearraylist 我有

maths

english

maths

hindi

english

所以我想要 o/p:

1_Maths

1_english

2_Maths hindi

2_english

我的代码是生成数组列表

Dim col As Integer = 0
Dim dt As New DataTable

Dim ArraySubject(0, Grd.Columns.Count - 1) As String
For i As Integer = 0 To Grd.Columns.Count - 1
   If Grd.Columns(i).Visible = True Then
      ArraySubject(0, col) = GvSearch.HeaderRow.Cells(i).Text 
      col += 1
    End If
Next

用 C# 回答也会对我有帮助。

Answer 1

我不太了解 VB.NET，所以这就是我认为您想要的 C#:

string[] subjects = new string[] { "maths", "english", "maths", "hindi", "english" };

Dictionary<string, int> subjectCounts = new Dictionary<string, int> ();
foreach (string subject in subjects) {
    if (subjectCounts.ContainsKey(subject))
        subjectCounts[subject]++;
    else
        subjectCounts.Add(subject, 1);
}

List<string> output = new List<string>();
foreach (KeyValuePair<string, int> pair in subjectCounts) {
    if (pair.Value > 1) {
        for (int i = 1; i <= pair.Value; i++)
            output.Add(i + "_" + pair.Key);
    } else {
        output.Add(pair.Key);
    }
}

foreach (string subject in output)
    Console.WriteLine(subject);

这个输出:

1_maths

2_maths

1_english

2_english

hindi

如果要按数字排序，在输出之前对数组进行排序即可。

output.Sort();

输出:

1_english

1_maths

2_english

2_maths

hindi