通用列表修改C＃中的属性值

Question

Lets say i have following class

public class abc
{
    int id;
    string name;
}

i am using this class as a collection of some data and my business logic appends some rows in it.

List<abc> lstData = GetData();

Now if i have to modify some property value lets say i want to modify the name property with some value.

string replaceName = 'jay';

so this jay should be in every row of the list in name property.

how to do this ? i think there is a convertAll method can we use that....

Answer 1

ConvertAll is usually used to create a new list , whereas it sounds like you just want to modify properties within existing objects. So I'd use:

foreach (abc value in lstData)
{
    value.name = replaceName;
}

(This code would look more idiomatic if you'd used names following the .NET naming conventions , by the way.)

Alternatively, you could use ConvertAll if you wanted to create new objects:

List<abc> newList = lstData.ConvertAll(old => new abc { 
    id = old.id,
    name = replaceName
});

That's using a lambda expression for the delegate, and an object initializer to set the properties in each new object. The exact way that you'd approach this would depend on your real class.

Answer 2

使用List.ForEach

lstData.ForEach(x => x.name = "jay");

Answer 3

您可以使用下面的LINQ运算符ForEach（）：

lstData.ForEach(data => data.Name = replaceName);

Answer 4

Do you mean you want to assign the same value to a property of all the object in the list? If yes then you loop over it:

foreach (var item in lstData)
{
    item.name = "jay";
}

Answer 5

I think in real life, when you want to modify Name , you must be having Id, so based on that you can find a single object to be modified in the list like:

 abc objAbc =(
    from emp 
    in lstData 
    where emp => emp.Id = someId 
    select emp)
    .SingleOrDefault(); 

Once you have objAbc you can do objAbc.Name = "New Name"

I hope that's what you want to know. you need to do using System.Linq I hope that's what you want to know. you need to do using System.Linq in order to use linq-to-object.

Happy coding