Loop through object variables with different numbe

2020-03-29 05:30发布

问题:

I have the following class:

public class Employees {
public string field1 { get; set; }
public string field2 { get; set; }
public string field3 { get; set; }
public string field4 { get; set; }
}

And i want to change values to all those members. so i can to something like that:

Employees.field1 = "ghgf";
Employees.field2 = "ghgf";
Employees.field3 = "ghgf";
Employees.field4 = "ghgf";

but it's very ugly. and the amount of members will be 30, so this is not a good way... I want to use for loop, that run over all the members and dynamic took the relevant field and change the value. for example:

for(int i=1; i<4; i++) {
var field = "field" + i;
Employees.field(the Var!!) = "fgdfd";
}

but in this line:

Employees.field(the Var!!) = "fgdfd";

I have a problem because field is the var that was defined in the for loop.

回答1:

You can do it the hard (and not correct, IMO) way, using reflection. But if you have 30 variable like this, change your approach: use a List<string>, or a Dictionary <whateverKey, string> to store all your fields



回答2:

If you really must do it using reflection, you can do it like so:

var employees = new Employees();
var type = employees.GetType();

for (int i = 1; i <= 4; ++i)
    type.GetProperty("field"+i).SetValue(employees, "abcde");

Console.WriteLine(employees.field1); // Prints "abcde"

As other folks have pointed out, using reflection in this way seems a little suspect. It looks like you should be doing it a different way, for example by using a Dictionary<string,string>.



回答3:

You can try using Reflection

Type type = typeof(Employees);
PropertyInfo pi =  this.GetType().GetProperty();
pi.SetField(this, value);

Here is the MSDN link : https://msdn.microsoft.com/en-us/library/ms173183.aspx



回答4:

Try this approach (using GetMembers()) to get all the members of a class and loop them.

Employees myEmployees = new Employees();
MemberInfo[] members = myType.GetMembers();

for (int i =0 ; i < members.Length ; i++)
{
    // Display name and type of the concerned member.
    Console.WriteLine( "'{0}' is a {1}", members[i].Name, members[i].MemberType);
}


回答5:

You can do it using reflexion like that:

        var myEmployees = new Employees();
        var properties = myEmployees.GetType().GetProperties();

        foreach (var field in properties)
        {
            field.SetValue(myEmployees, "NewValue");
        }

        // Print all field's values
        foreach (var item in properties)
        {
            Console.WriteLine(item.GetValue(myEmployees));
        }

Otherwise you can use a list or a dictionary or create a new struct that offre you more flexibility and let you able to control more properties of the field:

    struct FieldProperties
    {
        public string Name { get; set; }
        public string Value { get; set; }
        public string Type { get; set; }
        ...
    }


    List<FieldProperties> lst = new List<FieldProperties>();