[WCF]DomainServices客户端操作异常处理

作为个人备忘，不做排版。此扩展函数用于DomainServices的Load及SubmitChanges时处理Error信息，包括验证消息、实体冲突。

public static string ToErrorString(this System.ServiceModel.DomainServices.Client.OperationBase op)
{
    //来自http://www.cnblogs.com/ainijiutian/p/3616198.html
    if (op.HasError)
    {
        op.MarkErrorAsHandled();

        System.Text.StringBuilder sb = new System.Text.StringBuilder();
        if (op is System.ServiceModel.DomainServices.Client.LoadOperation)
        {
            var lo = op as System.ServiceModel.DomainServices.Client.LoadOperation;
            if (lo.ValidationErrors != null && lo.ValidationErrors.Any())
            {
                sb.Append("Validation Errors:
" + string.Join("
", lo.ValidationErrors.Select(t => t.ErrorMessage)) + "

");
            }
            sb.Append("Error message:
" + lo.Error.ToString());

            return sb.ToString();
        }
        else if (op is System.ServiceModel.DomainServices.Client.SubmitOperation)
        {
            var so = op as System.ServiceModel.DomainServices.Client.SubmitOperation;
            if (so.EntitiesInError != null && so.EntitiesInError.Any())
            {
                foreach (var e in so.EntitiesInError)
                {
                    sb.Append(so.EntitiesInError.First().GetType() + " " + e.ToString() + ":
");
                    if (e.HasValidationErrors)
                    {
                        sb.Append("Validation Errors:
" + string.Join("
", e.ValidationErrors.Select(t => t.ErrorMessage)) + "
");
                    }
                    if (!e.EntityConflict.IsDeleted && e.EntityConflict != null && e.EntityConflict.PropertyNames != null && e.EntityConflict.PropertyNames.Any())
                    {
                        sb.Append("Entity conflict:
" + string.Join(", ", e.EntityConflict.PropertyNames) + "
");
                    }
                }
                sb.Append("
");
            }
            sb.Append("Error message:
" + so.Error.ToString());
            //if (sb.ToString().Contains("STAMP")) //timestamp
            //{
            //    return "Document has been changed in other place,please undo the current changes and reopen .";
            //}
            //else
            //{
            //    return sb.ToString();
            //}
            return sb.ToString();
        }
    }
    return op.ToString();
}