從不同的值合並列表中的項目

Question

我有以下模型：

class serverMaster
{
    public string vm { get; set; }
    public string bm { get; set; }
    public string incrday { get; set; }
    public string incrtime { get; set; }
    public string fullday { get; set; }
    public string fulltime { get; set; }
    public string backupgroup { get; set; }
    public serverMaster(string vm1, string bm1, string incrday1, string incrtime1, string fullday1, string fulltime1, string backupgroup1)
    {
        vm = vm1;
        bm = bm1;
        incrday = incrday1;
        incrtime = incrtime1;
        fullday = fullday1;
        fulltime = fulltime1;
        backupgroup = backupgroup1;

    }
}

我有一個這樣的數據集：

如何使用 Linq 在第一列中查找重復項（例如合並 Aether）並連接其他字段。

理想情況下，我希望看到這樣的輸出：

Answer 1

您想要做的是在關鍵字段上使用GroupBy （根據您的評論和模型，我假設它是vm ，然后對其他字段執行聚合操作。從您的示例數據中，您要連接字符串：

var result = allItems.GroupBy(item => item.vm)
                     .Select(group => new serverMaster {
                         vm = group.Key,
                         incrday = string.Join(", ", group.Select(i => i.incrday)),
                         incrtime = string.Join(", ", group.Select(i => i.incrtime)),
                         fullday = string.Join(", ", group.Select(i => i.fullday)),
                         fulltime = string.Join(", ", group.Select(i => i.fulltime)),
                         backupgroup = string.Join(", ", group.Select(i => i.backupgroup))
                     }).ToList();

---

由於您沒有默認構造函數，您應該：

var result = allItems.GroupBy(item => item.vm)
                     .Select(group => new serverMaster (
                         group.Key,
                         string.Join(", ", group.Select(i => i.incrday)),
                         string.Join(", ", group.Select(i => i.incrtime)),
                         string.Join(", ", group.Select(i => i.fullday)),
                         string.Join(", ", group.Select(i => i.fulltime)),
                         string.Join(", ", group.Select(i => i.backupgroup))
                     )).ToList();

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