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C#. Set a member object value using reflection

I need your help with the following code below. Basically I have a class called "Job" which has some public fields. I'm passing to my method "ApplyFilter" two parameters "job_in" and "job_filters". First parameter contains actual data, and the second one has instructions (if any). I need to iterate through "job_in" object, read it's data, apply any instructions by reading "job_filters", modify data (if needed) and return it in a new "job_out" object. Everything works fine till i need to store my data in "job_out" object:

    public class Job
    {
        public string job_id = "";
        public string description = "";
        public string address = "";
        public string details = "";
    }

...

    private Job ApplyFilters(Job job_in, Job job_filters)
    {

        Type type = typeof(Job);
        Job job_out = new Job();
        FieldInfo[] fields = type.GetFields();

        // iterate through all fields of Job class
        for (int i = 0; i < fields.Length; i++)
        {
            List<string> filterslist = new List<string>();
            string filters = (string)fields[i].GetValue(job_filters);

            // if job_filters contaisn magic word "$" for the field, then do something with a field, otherwise just copy it to job_out object
            if (filters.Contains("$"))
            {
                filters = filters.Substring(filters.IndexOf("$") + 1, filters.Length - filters.IndexOf("$") - 1);
                // MessageBox.Show(filters);
                // do sothing useful...
            }
            else
            {
                // this is my current field value 
                var str_value = fields[i].GetValue(job_in);
                // this is my current filed name
                var field_name = fields[i].Name;

                //  I got stuck here :(
                // I need to save (copy) data "str_value" from job_in.field_name to job_out.field_name
                // HELP!!!

            }
        }
        return job_out;
    }

Please help. I've seen a few samples by using properties, but i'm pretty sure it is possible to do the same with fields as well. Thanks!

like image 839
Gary Avatar asked Nov 13 '11 18:11

Gary


1 Answers

Try this

public static void MapAllFields(object source, object dst)
{
    System.Reflection.FieldInfo[] ps = source.GetType().GetFields();
    foreach (var item in ps)
    {
        var o = item.GetValue(source);
        var p = dst.GetType().GetField(item.Name);
        if (p != null)
        {
            Type t = Nullable.GetUnderlyingType(p.FieldType) ?? p.FieldType;
            object safeValue = (o == null) ? null : Convert.ChangeType(o, t);
            p.SetValue(dst, safeValue);
        }
    }
}
like image 116
DeveloperX Avatar answered Sep 20 '22 22:09

DeveloperX