c# - 有没有办法将 SelectMany 用于字典

Question

我目前正在查询如下字典，

foreach (var instance in Dict)
{
   X += $"(Description = '{instance.Key}') OR ";
}

我可以使用SelectMany并准备字符串X吗？我还需要消除最后一个OR？

Dict.SelectMany(p=>p.Key.....) 

Answer 1

只需使用 string.Join和Select

var result = string.Join(" OR ",dict.Keys.Select(x=> $"Description = '{x}'"));

Full Demo Here

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其他资源

Dictionary.Keys Property

Gets a collection containing the keys in the Dictionary<TKey,TValue>.

String.Join Method

Concatenates the elements of a specified array or the members of a collection, using the specified separator between each element or member.

Enumerable.Select Method

Projects each element of a sequence into a new form.