创建一个dynamics 365 CRM online plugin (五) - Images in Plugin

时间：2019-04-22 00:58:27 阅读：227 评论：0 收藏：0 [点我收藏+]

标签：cut logic form from str ade post src led

Snapshots of the primary entity‘s attributes from database before(pre) and after (post) the core platform operation.

怎么理解这句话呢

简单的我们可以理解PreOperation与PostOperation的 entity中数据的镜像.

使用Pre-Entity镜像的一些案例:

1. 如果你需要对original data在modification之前做使用.

2. 如果你需要form的original data没有被modified修改之前做读取.

PS: local name 为field的label name/entity name. Schema name 为数据库中field的名字　　

这次我们将修改leader 中的filedbusiness telephone number(logical name 为telephone1)

我们将plugin中try模块里面的代码用以下代码覆盖掉

我们可以看到,我们获取了modifiedBusinessPhone 为update之后的值.

我们又使用了preImage这个value 从PreEntityImages镜像中获取original value 为originalBusinessPhone

// Plug-in business logic goes here.  


                    //Pre and post entity images
                    // Snapshots of the primary entity‘s attributes from database before (pre) and after (post) the core platfomr operation.

                    // This is modified business phone number
                    var modifiedBusinessPhone = entity.Attributes["telephone1"].ToString();

                    // Retrieve preEntity Images
                    var preImage = (Entity)context.PreEntityImages["PreImage"];

                    // Normally we don‘t retrieve post entity images with following reason
                    // 1. After the postOperation, we are on the current situation modifed data
                    // 2. When retrieve the postEntityImages, due to it is not created, the entity will be null.
                    // Entity postImage = (Entity)context.PostEntityImages["PostImage"];

                    // Retrieve original business phone number
                    var originalBusinessPhone = preImage.Attributes["telephone1"].ToString();

                    // Display the information in the error log
                    throw new InvalidPluginExecutionException("Phone number is changed from" + originalBusinessPhone + " to " + modifiedBusinessPhone);