c# - How to get a dump of all local variables?

Question

How can I get a dump of all local & session variables when an exception occurs? I was thinking of writing some sort of reflection based function that would interrogate the calling function & create a dump of variables & values.

Is there an existing library that I can use?

UPDATE

After speaking to a colleague, I was pointed to AOP or Aspect Oriented Programming. Here is what I understand ... Using AOP, one would simple decorate the methods & classes with certain attributes. AOP framework then injects code in or around these classes & methods. There are two separate kinds of framework, one that injects code & then compiles the assembly & the second simply uses reflection & traps the call which you have decorated and wraps whatever code around the method at runtime.

I hope all that makes sense. I will be doing more research on this & post my approach.

Thanks guys ...

Answer 1

I'm not sure if this is what you're looking for. But if you're in a catch-block you can get all fields and properties of this class in the following way:

try
{
    double d = 1 / 0;
}
catch (Exception ex)
{
    var trace = new System.Diagnostics.StackTrace();
    var frame = trace.GetFrame(1);
    var methodName = frame.GetMethod().Name;
    var properties = this.GetType().GetProperties();
    var fields = this.GetType().GetFields(); // public fields
    // for example:
    foreach (var prop in properties)
    {
        var value = prop.GetValue(this, null);
    }
    foreach (var field in fields)
    {
        var value = field.GetValue(this);
    }
    foreach (string key in Session) 
    {
        var value = Session[key];
    }
}

I've showed how to get the method name where the exception occured only for the sake of completeness.

• Type.GetProperties Method
• Type.GetFields Method
• PropertyInfo.GetValue Method
• FieldInfo.GetValue Method
• StackTrace Class

With BindingFlags you can specify constraints, for example that you only want properties of this class and not from inherited:

Using GetProperties() with BindingFlags.DeclaredOnly in .NET Reflection

Of course the above should give you only a starting-point how to do it manually and you should encapsulate all into classes. I've never used it myself so it's untested.