public CompilerErrorCollection SetExpression(string expression)
{
CompilerErrorCollection compilerErrors = new CompilerErrorCollection();
IUnitPriceExpression newExpression = CreateDynamicExpression(expression, out compilerErrors);
if (!compilerErrors.HasErrors)
{
this.expression = newExpression;
}
return(compilerErrors);
}
private static IUnitPriceExpression CreateDynamicExpression(string expression, out CompilerErrorCollection errors)
{
errors = new CompilerErrorCollection();
if (String.IsNullOrEmpty(expression))
{
return(null);
}
CompilerParameters parms = new CompilerParameters();
parms.GenerateExecutable = false;
parms.GenerateInMemory = true;
parms.IncludeDebugInformation = false;
string assemblyFileName = Path.GetFileName(Assembly.GetExecutingAssembly().Location);
parms.ReferencedAssemblies.Add("System.dll");
parms.ReferencedAssemblies.Add(assemblyFileName);
CodeDomProvider compiler = CSharpCodeProvider.CreateProvider("CSharp");
string classCode = string.Format(ClassTemplate, typeof(UnitPriceConverter).FullName, expression);
CompilerResults compilerResults = compiler.CompileAssemblyFromSource(parms, classCode);
if (compilerResults.Errors.HasErrors)
{
errors = compilerResults.Errors;
return(null);
}
Assembly assembly = compilerResults.CompiledAssembly;
IUnitPriceExpression unitPriceExpression = assembly.CreateInstance("DynamicUnitPriceExpression") as IUnitPriceExpression;
return(unitPriceExpression);
}
