public static string GetMemberPath([NotNull] LambdaExpression expression, string separator = ".")
{
var ret = new StringBuilder();
Expression current = expression.Body;
while (current.NodeType != ExpressionType.Parameter)
{
// This happens when a value type gets boxed
if (current.NodeType == ExpressionType.Convert || current.NodeType == ExpressionType.ConvertChecked)
{
var ue = (UnaryExpression)current;
current = ue.Operand;
continue;
}
string memberName;
var methodCallExpression = current as MethodCallExpression;
if (methodCallExpression != null)
{
if (methodCallExpression.Method.Name != "get_Item")
{
throw BindingExceptionManager.InvalidBindingMemberExpression();
}
string s = string.Join(",", methodCallExpression.Arguments.Cast <ConstantExpression>().Select(e => e.Value));
memberName = "[" + s + "]";
current = methodCallExpression.Object;
}
else if (current.NodeType != ExpressionType.MemberAccess)
{
throw BindingExceptionManager.InvalidBindingMemberExpression();
}
else
{
var me = (MemberExpression)current;
memberName = me.Member.Name;
current = me.Expression;
}
if (ret.Length != 0)
{
ret.Insert(0, separator);
}
ret.Insert(0, memberName);
if (current == null)
{
break;
}
}
return(ret.ToString());
}
internal static bool TryGetMemberPath(Expression expression, string separator, bool throwOnError, out Expression lastExpression, out string path)
{
lastExpression = expression;
path = null;
if (expression == null)
{
return(false);
}
var ret = new StringBuilder();
bool error = false;
while (lastExpression.NodeType != ExpressionType.Parameter)
{
if (error)
{
if (throwOnError)
{
throw BindingExceptionManager.InvalidBindingMemberExpression();
}
path = ret.ToString();
return(false);
}
// This happens when a value type gets boxed
if (lastExpression.NodeType == ExpressionType.Convert ||
lastExpression.NodeType == ExpressionType.ConvertChecked)
{
var ue = (UnaryExpression)lastExpression;
lastExpression = ue.Operand;
continue;
}
string memberName;
var methodCallExpression = lastExpression as MethodCallExpression;
if (methodCallExpression != null)
{
var memberAttribute = methodCallExpression.Method
.GetAttributes()
.OfType <BindingSyntaxMemberAttribute>()
.FirstOrDefault();
if (memberAttribute != null)
{
if (methodCallExpression.Arguments.Count != 1 && methodCallExpression.Arguments.Count != 2)
{
error = true;
continue;
}
lastExpression = methodCallExpression.Arguments[0];
if (methodCallExpression.Arguments.Count == 2)
{
if (!methodCallExpression.Arguments[1].TryGetStaticValue(out memberName, false))
{
error = true;
continue;
}
}
else
{
memberName = memberAttribute.GetMemberName(methodCallExpression.Method);
}
}
else
{
if (methodCallExpression.Method.Name != "get_Item")
{
error = true;
continue;
}
var builder = new StringBuilder("[");
var args = methodCallExpression.Arguments;
for (int i = 0; i < args.Count; i++)
{
object value;
if (!args[i].TryGetStaticValue(out value, false))
{
error = true;
break;
}
if (i != 0)
{
builder.Append(",");
}
builder.Append(value.ToStringValue());
}
if (error)
{
continue;
}
builder.Append("]");
memberName = builder.ToString();
lastExpression = methodCallExpression.Object;
}
}
else if (lastExpression.NodeType != ExpressionType.MemberAccess)
{
error = true;
continue;
}
else
{
var me = (MemberExpression)lastExpression;
memberName = me.Member.Name;
lastExpression = me.Expression;
}
if (ret.Length != 0 && ret[0] != '[')
{
ret.Insert(0, separator);
}
ret.Insert(0, memberName);
if (lastExpression == null)
{
break;
}
}
path = ret.ToString();
return(true);
}