问从.net 4.8迁移到.net 6后LINQ查询速度较慢EN这段代码使用Linq对List列表进行筛选、分组、排序等一系列操作展示了Linq的强大和便捷，那么我们为什么需要学习Linq？可以看到这样一堆逻辑只几行Linq很快就可以实现，如果要我们自己实现方法去处理这个List肯定是比较繁琐的。 Linq是什么？如下是官方文档对于Linq的描述:
This is based on two or more columns in the list currently I have three columns but would like to build a helper on the the columns that them as duplicate. The rules are to check by Name, Category and Weight if there are duplicates in the list mark the Status field with -1 for the...
Sometimes you need to find the duplicates in a list. I’m currently developing a little utility that tests code in a word processing document (now posted, you can find it here). Each code snippet in the document has an identifier, and one of the rules that I’m imposing on this code...
Getting complete information is a good thing, but sometimes it's too much of a good thing, especially when the information contains duplicates. For instance, this query returns just the author IDs for each available book: Copy Dim justIDs = From bk In Library _ Select bk.AuthorID Show...
linq 检查IEnumerable< T>中是否存在具有重复属性的项其可以读作：* 当 *All* 项可以 *Add-艾德为一...
linq 检查IEnumerable< T>中是否存在具有重复属性的项其可以读作：* 当 *All* 项可以 *Add-艾德为一...
products.Distinct(newProductComparer());foreach(varproductinnoduplicates) Console.WriteLine(product.Name +" "+ product.Code);/* This code produces the following output: apple 9 orange 4 lemon 12 */
The Enumerable class plays an important role in every LINQ query you create. For example, imagine that your project includes a Product class and a generic List of Product instances (as in the sample project). You've created an instance of the SimpleDataContext class from the sample that...
The Enumerable class plays an important role in every LINQ query you create. For example, imagine that your project includes a Product class and a generic List of Product instances (as in the sample project). You've created an instance of the SimpleDataContext class from the sample that...
IEnumerable<MyProduct> noduplicates = products.Distinct(); foreach (var product in noduplicates) Console.WriteLine(product.Name + " " + product.Code); /* This code produces the following output: apple 9 orange 4 lemon 12 */ Remarques Cette méthode est implémentée à l’aide de l’ex...