Solved

Eval a string in C#

Posted on 2004-08-11
10
20,696 Views
Last Modified: 2012-06-27
How do I evaluate a string in C#?  Example:

string myVarName = "sTest";
eval("string "+myVarName+" = \"<p>Value of string goes here</p>\"");
Response.Write(eval(myBarName));


Should output:
<p>Value of string goes here</p>
0
Comment
Question by:hendridm
  • 3
  • 3
  • 2
  • +2
10 Comments
 
LVL 5

Expert Comment

by:jjacksn
ID: 11774908
This is not really want you want, but might point you in the correct direction

using System;
using System.Reflection ;

namespace ConsoleApplication4
{
     /// <summary>
     /// Summary description for Class1.
     /// </summary>
     class Class1
     {

          private class foo {
               private int bar;
               public int Bar {
                    get { return bar; }
                    set { bar = value ; }
               }
               public foo() {}
          }


          static object GetProperty(string Name, object Obj) {
               PropertyInfo p = Obj.GetType().GetProperty(Name) ;
               if(p!=null) {
                    if(p.CanRead) {
                         return p.GetValue(Obj, null) ;
                    } else {
                         throw new System.Exception(Name + " is a WriteOnly property cannot read value") ;
                    }
               } else {
                    throw new System.ArgumentOutOfRangeException(Name) ;
               }
          }

          [STAThread]
          static void Main(string[] args)
          {
               foo f = new foo();
               f.Bar = 37;
               object o = GetProperty("Bar", f);
               Console.WriteLine("f.Bar = " + o.ToString() );
          }
     }
}
0
 
LVL 5

Assisted Solution

by:jjacksn
jjacksn earned 50 total points
ID: 11774919
0
 
LVL 5

Assisted Solution

by:jjacksn
jjacksn earned 50 total points
ID: 11774954
After reading around, I don't think there is an equivelent to the JScript eval command.  

http://www.dotnet247.com/247reference/msgs/6/31515.aspx.  If you want to literally execute the strings, it looks like you will have to compile assemblies at run time.
0
Live: Real-Time Solutions, Start Here

Receive instant 1:1 support from technology experts, using our real-time conversation and whiteboard interface. Your first 5 minutes are always free.

 
LVL 37

Expert Comment

by:gregoryyoung
ID: 11775000
theres a more recent thread (from yesterday in fact) http://www.experts-exchange.com/Programming/Programming_Languages/C_Sharp/Q_21088360.html

System.Web.UI.DataBinder.Eval() is what you want.
0
 
LVL 8

Author Comment

by:hendridm
ID: 11775017
Ok, thanks.  To be more specific, is there a way to do this?

string myVar = "Literal1";
Literal1.Text = "Lorem Ipsum";

Is there a way to programmatically specify 'Literal1', like so:

string myVar = "Literal1";
<name of variable in 'myVar'>.Text = "Lorem Ipsum";

If not, no problem.  You essentially answered my question anyway.
0
 
LVL 37

Assisted Solution

by:gregoryyoung
gregoryyoung earned 25 total points
ID: 11775043
for that you would be best off to use reflections ...
0
 
LVL 96

Expert Comment

by:Bob Learned
ID: 11783603
Are you talking about using Inline code with ASP.NET?

Bob
0
 
LVL 96

Expert Comment

by:Bob Learned
ID: 11783683
Something like this:

(1)  Define a page-level variable in public variable in the code-behind:

    Public var_value As Integer = 5

(2)  Use the HTML design to use the following inline code:

<p><%=var_value%></p>

The page will display 5 within the block.

Bob
0
 
LVL 37

Expert Comment

by:gregoryyoung
ID: 11785062
for the above you could also use FindControl() ...
0
 
LVL 20

Accepted Solution

by:
ihenry earned 175 total points
ID: 11803153
0

Featured Post

Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Turn on intranet settings 1 56
rest webservice call over https via c# 6 37
What is "public object" in C#? 3 45
Hey!!!! 1 20
Article by: Ivo
C# And Nullable Types Since 2.0 C# has Nullable(T) Generic Structure. The idea behind is to allow value type objects to have null values just like reference types have. This concerns scenarios where not all data sources have values (like a databa…
Introduction Although it is an old technology, serial ports are still being used by many hardware manufacturers. If you develop applications in C#, Microsoft .NET framework has SerialPort class to communicate with the serial ports.  I needed to…
This tutorial gives a high-level tour of the interface of Marketo (a marketing automation tool to help businesses track and engage prospective customers and drive them to purchase). You will see the main areas including Marketing Activities, Design …
This video shows how to use Hyena, from SystemTools Software, to bulk import 100 user accounts from an external text file. View in 1080p for best video quality.

785 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question