c# - Setting a field of a class's instance with reflection -

i have following issue related reflection , have method looks :

  [testmethod()]  public void steamaccess()         {             testread = new testread();             steammap = new steammap();             // preparing parameters of csv actions             a.writemessageparams.uiitemedittext = testcontext.datarow["searchquery"].tostring();             //read , execute testmethod             testread.read(a, testcontext);         } 

this codeduitest, steammap class (uitest map). writemessageparams class, real method writemessage class allows me override string gets used tests writemessage method, , plan make part of code more dynamically in read method. :

   a.writemessageparams.uiitemedittext = testcontext.datarow["searchquery"].tostring(); 

my problem happens in testread.read context follows :

when method running have access actions respective instance ( a in case ) , if supposed have use a.writemessageparams.uiitemedittext context know it, how info isn't problem, problem how make mentioned code run dynamically have tried :

/* i've done because know each method supposed end params, example method called writemessage, it's class called writemessageparams*/  public void read(object obj, testcontext testcontext) { //simplified code //trying access/get current instance's writemessageparam class  object testobj = obj.gettype().getmember(submethod.code + "param");  //null messagebox.show(testobj.gettype().tostring());  // trying access uiitemedittext field ( declared public) , modify accordingly  fieldinfo submethodfield = testobj.gettype().getfield("uiitemedittext"); submethodfield.setvalue(testobj,testcontext.datarow[submethod.csvcolumn].tostring()); } 

i've had read on article , tried few things https://msdn.microsoft.com/en-us/library/6z33zd7h%28v=vs.110%29.aspx

my problem have object of instance , try access object's class , modify class's field .

i'd appreciate help, thanks

edit 1: how class i'm trying access looks :

public partial class steammap     { //simplified classes/methods interest me              public virtual writemessageparams writemessageparams         {                         {                 if ((this.mwritemessageparams == null))                 {                     this.mwritemessageparams = new writemessageparams();                 }                 return this.mwritemessageparams;             }         }  public class writemessageparams     {          #region fields         /// <summary>         /// type 'test' in text box         /// </summary>         public string uiitemedittext = "test";         #endregion     }     } 

edit 2 - i've tried using getnestedtype, still no success....

object testobj = obj.gettype().getnestedtype("writemessageparams",bindingflags.public);  messagebox.show(testobj.gettype().tostring()); 

if understand you, have class

public partial class steammap {        private writemessageparams mwritemessageparams ;      public virtual writemessageparams  writemessageparams1     {                 {             if ((this.mwritemessageparams == null))             {                 this.mwritemessageparams = new writemessageparams();             }             return this.mwritemessageparams;         }     }      public class writemessageparams     {                     public string uiitemedittext = "test";            } } 

(your code doesn't compile because have writemessageparams both class , property, have changed property writemessageparams1)

and want change uiitemedittext, can like

public void updateui(object obj, string newvalue) {     var property = obj.gettype().getproperty("writemessageparams1");      var writemessageparams1 = property.getvalue(obj);       var uifld = wp.gettype().getfield("uiitemedittext");      uifld.setvalue(writemessageparams1, newvalue);  } 

which can called like

steammap sm = new steammap(); write(sm, "hello");   

the key use .getproperty property , .getfield field.