public Expression GetExpressionTree()
{
if (this.IsMetadataCached)
{
if (this.expressionTree == null)
{
string validationError;
// it's safe to create this CodeActivityMetadata here,
// because we know we are using it only as lookup purpose.
CodeActivityMetadata metadata = new CodeActivityMetadata(this, this.GetParentEnvironment(), false);
CodeActivityPublicEnvironmentAccessor publicAccessor = CodeActivityPublicEnvironmentAccessor.CreateWithoutArgument(metadata);
try
{
this.expressionTree = this.CompileLocationExpression(publicAccessor, out validationError);
if (validationError != null)
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.ExpressionTamperedSinceLastCompiled(validationError)));
}
}
finally
{
metadata.Dispose();
}
}
Fx.Assert(this.expressionTree.NodeType == ExpressionType.Lambda, "Lambda expression required");
return(ExpressionUtilities.RewriteNonCompiledExpressionTree((LambdaExpression)this.expressionTree));
}
else
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.ActivityIsUncached));
}
}
public Expression GetExpressionTree()
{
if (this.IsMetadataCached)
{
if (this.expressionTree == null)
{
// it's safe to create this CodeActivityMetadata here,
// because we know we are using it only as lookup purpose.
var metadata = new CodeActivityMetadata(this, this.GetParentEnvironment(), false);
var publicAccessor = CodeActivityPublicEnvironmentAccessor.CreateWithoutArgument(metadata);
try
{
this.expressionTree = VisualBasicHelper.Compile <TResult>(this.ExpressionText, publicAccessor, false);
}
catch (SourceExpressionException e)
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.VBExpressionTamperedSinceLastCompiled(e.Message)));
}
finally
{
metadata.Dispose();
}
}
Fx.Assert(this.expressionTree.NodeType == ExpressionType.Lambda, "Lambda expression required");
return(ExpressionUtilities.RewriteNonCompiledExpressionTree((LambdaExpression)this.expressionTree));
}
else
{
throw FxTrace.Exception.AsError(new InvalidOperationException(SR.ActivityIsUncached));
}
}