27 lines
965 B
Markdown
27 lines
965 B
Markdown
---
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title: Count
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localeTitle: 计数
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---
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＃ 任何 返回序列中满足条件的元素计数。 ###签名
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```csharp
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Enumerable.Count<TSource> Method (IEnumerable<TSource>, Func<TSource, Boolean>)
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```
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##例子
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```csharp
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var fruits = new List<Fruit>() {
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new Fruit() { Id = 1, Name = "Orange", Color = "Orange", Quantity: 3 },
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new Fruit() { Id = 2, Name = "Strawberry", Color = "Red", Quantity: 12 },
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new Fruit() { Id = 3, Name = "Grape", Color = "Purple", Quantity: 25 },
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new Fruit() { Id = 4, Name = "Pineapple", Color = "Yellow", Quantity: 1 },
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new Fruit() { Id = 5, Name = "Apple", Color = "Red", Quantity: 5 },
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new Fruit() { Id = 6, Name = "Mango", Color = "Yellow", Quantity: 2 }
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};
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// Count of Fruit with Color Red.
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var yellowCount = fruits.Count(f => f.Color == "Red"); // 2
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// Count of Fruit with Quantity > 2
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var quantityOverTwo = fruits.Count(f => f.Quantity > 2); // 4
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``` |