32 lines
1018 B
Markdown
32 lines
1018 B
Markdown
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---
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title: Where
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localeTitle: 哪里
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---
# 哪里
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过滤数据集中的元素。
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### 签名
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```csharp
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Enumerable.Where<TSource> Method (IEnumerable<TSource>, Func<TSource, Boolean>)
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```
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## 例
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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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// Fruits with more than 3 items
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var moreThanThree = fruits.Where(f => f.Quantity > 3).ToList(); // { Strawberry, Grape, Apple }
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// Fruits that are not red
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var notRed = fruits.Where(f => f.Color != "Red").ToList(); // { Orange, Grape, Pineapple, Mango }
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```
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