I have this class as part of a Consol application.
using System;
namespace Bugreport
{
/// <summary>
/// This class tries to use the Class/Struct combination.
/// </summary>
class Class1
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main(string[] args)
{
//
// TODO: Add code to start application here
//
}
public void test(){
CLS myCLS = new CLS();
///this statement is giving a compile time error:
///D:\ITSSjain\Vis ual Studio Projects\Bugrep ort\Class1.cs(2 6): Cannot modify the return value of 'Bugreport.CLS. myStruct' because it is not a variable.
myCLS.myStruct. Prop1 = "This is a test string";
}
}
/// <summary>
/// Test Structure
/// </summary>
public struct STRUCT{
public string Prop1;
public string Prop2;
}
/// <summary>
/// test class which has a public property exposing the above struct.
/// </summary>
public class CLS{
private STRUCT _myStruct;
public CLS(){
myStruct = new STRUCT();
}
public STRUCT myStruct{
get{
return _myStruct;
}
set{
_myStruct = value;
}
}
}
}
Why am I getting the Compile time error?
thanks
sachin jain 2 11260
Sachin,
This happens because you are using a struct, and structs have "copy by
value" semantics.
In your statement: myCLS.myStruct. Prop1 = "This is a test string";
when you call myCLS.myStruct, the myStruct property is returning a copy of
the property value. Referring to a property is then referring to a property
on the *copy*, and if the compiler allowed it, it would be a meaningless
statement, so we don't allow you to say it.
In general, you should stick with classes unless you're really sure you need
to use a struct. If you did want to do this with a struct, you'd have to
write:
MyStruct temp = myCLS.myStruct;
temp.Prop1 = "This is a test string";
myCLS.myStruct = temp;
--
Eric Gunnerson
Visit the C# product team at http://www.csharp.net
Eric's blog is at http://weblogs.asp.net/ericgu/
This posting is provided "AS IS" with no warranties, and confers no rights.
"SACHIN" <an*******@disc ussions.microso ft.com> wrote in message
news:AF******** *************** ***********@mic rosoft.com... I have this class as part of a Consol application. using System;
namespace Bugreport { /// <summary> /// This class tries to use the Class/Struct combination. /// </summary> class Class1 { /// <summary> /// The main entry point for the application. /// </summary> [STAThread] static void Main(string[] args) { // // TODO: Add code to start application here // }
public void test(){ CLS myCLS = new CLS(); ///this statement is giving a compile time error: ///D:\ITSSjain\Vis ual Studio Projects\Bugrep ort\Class1.cs(2 6): Cannot
modify the return value of 'Bugreport.CLS. myStruct' because it is not a
variable. myCLS.myStruct. Prop1 = "This is a test string"; } } /// <summary> /// Test Structure /// </summary> public struct STRUCT{ public string Prop1; public string Prop2; }
/// <summary> /// test class which has a public property exposing the above struct. /// </summary> public class CLS{ private STRUCT _myStruct; public CLS(){ myStruct = new STRUCT(); } public STRUCT myStruct{ get{ return _myStruct; } set{ _myStruct = value; } } } }
Why am I getting the Compile time error? thanks sachin jain
Hi Sachin
You can't access the members of a property directly. Try saving myCLS.myStruct into a temporary variable, modifying it, then setting myCLS.myStruct to it.
Either that, or you could change the properties to return the STRUCT's fields, instead of the whole STRUCT.
Hope that helps
-Chris
-------------------- Thread-Topic: C# - Struct in a class.. can not access properties of the struct thread-index: AcPkOdzeepjnEon lTke+XEEwEPD4gg == X-Tomcat-NG: microsoft.publi c.dotnet.genera l From: =?Utf-8?B?U0FDSElO?= <an*******@disc ussions.microso ft.com> Subject: C# - Struct in a class.. can not access properties of the struct Date: Mon, 26 Jan 2004 10:26:06 -0800 Lines: 60 Message-ID: <AF************ *************** *******@microso ft.com> MIME-Version: 1.0 Content-Type: text/plain; charset="Utf-8" Content-Transfer-Encoding: 7bit X-Newsreader: Microsoft CDO for Windows 2000 Content-Class: urn:content-classes:message Importance: normal Priority: normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.3790.0 Newsgroups: microsoft.publi c.dotnet.genera l Path: cpmsftngxa07.ph x.gbl Xref: cpmsftngxa07.ph x.gbl microsoft.publi c.dotnet.genera l:122648 NNTP-Posting-Host: tk2msftcmty1.ph x.gbl 10.40.1.180 X-Tomcat-NG: microsoft.publi c.dotnet.genera l
I have this class as part of a Consol application.
using System;
namespace Bugreport
{
/// <summary>
/// This class tries to use the Class/Struct combination.
/// </summary>
class Class1
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main(string[] args)
{
//
// TODO: Add code to start application here
//
}
public void test(){
CLS myCLS = new CLS();
///this statement is giving a compile time error:
///D:\ITSSjain\Vis ual Studio Projects\Bugrep ort\Class1.cs(2 6): Cannot modify the return value of 'Bugreport.CLS. myStruct' because it is not a variable.
myCLS.myStruct. Prop1 = "This is a test string";
}
}
/// <summary>
/// Test Structure
/// </summary>
public struct STRUCT{
public string Prop1;
public string Prop2;
}
/// <summary>
/// test class which has a public property exposing the above struct.
/// </summary>
public class CLS{
private STRUCT _myStruct;
public CLS(){
myStruct = new STRUCT();
}
public STRUCT myStruct{
get{
return _myStruct;
}
set{
_myStruct = value;
}
}
}
}
Why am I getting the Compile time error?
thanks
sachin jain
--
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I have this class as part of a Consol application.
using System;
namespace Bugreport
{
/// <summary>
/// This class tries to use the Class/Struct combination.
/// </summary>
class Class1
{
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