27 lines
1.1 KiB
Markdown
27 lines
1.1 KiB
Markdown
---
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title: LastOrDefault
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localeTitle: LastOrDefault
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---
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＃ 任何 返回序列中满足条件的最后一个元素，如果未找到任何元素，则返回默认值 ###签名
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```csharp
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Enumerable.LastOrDefault<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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// Returns the last fruit where the Color is Yellow
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var lastYellow = fruits.LastOrDefault(f => f.Color == "Yellow"); // Mango
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// Returns the last fruit where the quantity is 20
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var lastQuantityOfTwenty = fruits.LastOrDefault(f => f.Quantity == 20); // null
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``` |