Use image column data

The following static GetImageColumnMaxSizeInKb method returns the MaxSizeInKB value for an ImageAttributeMetadata column.

/// <summary>
/// Retrieves the MaxSizeInKb property of an image column.
/// </summary>
/// <param name="service">IOrganizationService</param>
/// <param name="entityLogicalName">The logical name of the table that has the column</param>
/// <param name="imageColumnLogicalName">The logical name of the image column.</param>
/// <returns></returns>
/// <exception cref="Exception"></exception>
public static int GetImageColumnMaxSizeInKb(
   IOrganizationService service, 
   string entityLogicalName, 
   string imageColumnLogicalName) 
{

   RetrieveAttributeRequest retrieveAttributeRequest = new() { 
         EntityLogicalName = entityLogicalName,
         LogicalName = imageColumnLogicalName
   };

   RetrieveAttributeResponse retrieveAttributeResponse;
   try
   {
         retrieveAttributeResponse = (RetrieveAttributeResponse)service.Execute(retrieveAttributeRequest);
   }
   catch (Exception)
   {
         throw;
   }

   if (retrieveAttributeResponse.AttributeMetadata is ImageAttributeMetadata imageColumn)
   {
         return imageColumn.MaxSizeInKB.Value;
   }
   else
   {
         throw new Exception($"{entityLogicalName}.{imageColumnLogicalName} is not a image column.");
   }
}

More information:

• RetrieveAttributeRequest Class
• ImageAttributeMetadata.MaxSizeInKB

The following request returns the MaxSizeInKB value for an ImageAttributeMetadata column with the logical name sample_imagecolumn in the account table.

Request:

GET [Organization Uri]/api/data/v9.2/EntityDefinitions(LogicalName='account')/Attributes(LogicalName='sample_imagecolumn')/Microsoft.Dynamics.CRM.ImageAttributeMetadata?$select=MaxSizeInKB HTTP/1.1
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json

Response:

HTTP/1.1 200 OK
Content-Type: application/json; odata.metadata=minimal
OData-Version: 4.0

{
  "@odata.context": "[Organization Uri]/api/data/v9.2/$metadata#EntityDefinitions('account')/Attributes/Microsoft.Dynamics.CRM.ImageAttributeMetadata(MaxSizeInKB)/$entity",
  "MaxSizeInKB": 102400,
  "MetadataId": "f315e7f1-6355-ed11-bba3-000d3a9933c9"
}

More information:

• Query table definitions using the Web API > Retrieving attributes
• ImageAttributeMetadata EntityType

The static PrintFullSizedImageColumns method will write the names of the table and image columns that can store full-sized images.

static void PrintFullSizedImageColumns(IOrganizationService service)
{
    QueryExpression query = new QueryExpression("attributeimageconfig")
    {
        ColumnSet = new ColumnSet("parententitylogicalname", "attributelogicalname"),
        Criteria = new FilterExpression(LogicalOperator.And)
        {
            Conditions =
            {
                new ConditionExpression(
                    attributeName: "canstorefullimage",
                    conditionOperator: ConditionOperator.Equal,
                    value: true)
            }
        }
    };

    EntityCollection response = service.RetrieveMultiple(query);
    foreach (Entity record in response.Entities)
    {
        Console.WriteLine($"{record["parententitylogicalname"]}.{record["attributelogicalname"]}");
    }
}

Output

account.sample_sampleimage

This request will return the names of the table and image columns that can store full-sized images.

Request:

GET [Organization URI]/api/data/v9.2/attributeimageconfigs?$select=parententitylogicalname,attributelogicalname&$filter=canstorefullimage eq true HTTP/1.1
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json

Response:

HTTP/1.1 200 OK
Cache-Control: no-cache
Allow: OPTIONS,GET,HEAD,POST
Content-Type: application/json; odata.metadata=minimal; odata.streaming=true
OData-Version: 4.0

{
  "@odata.context": "[Organization URI]/api/data/v9.2/$metadata#attributeimageconfigs(parententitylogicalname,attributelogicalname)",
  "value": [
    {
      "@odata.etag": "W/\"76501240\"",
      "parententitylogicalname": "account",
      "attributelogicalname": "sample_sampleimage",
      "attributeimageconfigid": "b8c1750f-c24f-ea11-a813-000d3a5391c8"
    }
  ]
}

The static PrintPrimaryImageColumns method below will write the table and image column names of all primary image columns.

static void PrintPrimaryImageColumns(IOrganizationService service)
{
    QueryExpression query = new QueryExpression("entityimageconfig")
    {
        ColumnSet = new ColumnSet("parententitylogicalname", "primaryimageattribute"),
    };

    EntityCollection response = service.RetrieveMultiple(query);
    foreach (Entity record in response.Entities)
    {
        Console.WriteLine($"{record["parententitylogicalname"]}.{record["primaryimageattribute"]}");
    }
}

Output

account.sample_sampleimage

More information: Build queries with QueryExpression

The request below will return the table and image column names of all primary image columns.

Request:

GET [Organization URI]/api/data/v9.2/entityimageconfigs?$select=parententitylogicalname,primaryimageattribute HTTP/1.1
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json

Response:

HTTP/1.1 200 OK
Cache-Control: no-cache
Allow: OPTIONS,GET,HEAD,POST
Content-Type: application/json; odata.metadata=minimal; odata.streaming=true
OData-Version: 4.0

{
  "@odata.context": "[Organization URI]/api/data/v9.2/$metadata#entityimageconfigs(parententitylogicalname,primaryimageattribute)",
  "value": [
    {
      "@odata.etag": "W/\"76501240\"",
      "parententitylogicalname": "account",
      "primaryimageattribute": "sample_sampleimage",
      "entityimageconfigid": "b8c1750f-c24f-ea11-a813-000d3a5391c8"
    }
  ]
}

More information: Query data using the Web API

The following static RetrieveAndUpdateImageColumn method retrieves a byte[] image value from a column, saves it locally and uploads a new image.

static void RetrieveAndUpdateImageColumn(
    IOrganizationService service,
    Guid accountid,
    string imageColumnLogicalName) 
{

    // Retrieve account with image
    Entity account = service.Retrieve(
        entityName: "account",
        id: accountid, 
        columnSet: new ColumnSet(imageColumnLogicalName));

    // Save the image retrieved
    File.WriteAllBytes(
        path: "original_image.png",
        bytes: account.GetAttributeValue<byte[]>(imageColumnLogicalName));


    // Instantiate a new entity for update with new image
    Entity accountForUpdate = new("account") { 
        Attributes = {
            { "accountid", accountid },
            { imageColumnLogicalName , File.ReadAllBytes("new_image.png")}
        }
    };

    // Update the account
    service.Update(accountForUpdate);               
}

More information:

• Retrieve a table row using the SDK for .NET
• Update and delete table rows using the SDK for .NET

With Web API, the property values are base 64 encoded string values representing the byte[] data.

This request returns an image column named sample_imagecolumn with an account record:

Request:

GET [Organization Uri]/api/data/v9.2/accounts(<accountid>)?$select=sample_imagecolumn HTTP/1.1
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json

Response:

HTTP/1.1 200 OK
ETag: W/"76796548"
OData-Version: 4.0

{
  "@odata.context": "[Organization Uri]/api/data/v9.2/$metadata#accounts(sample_imagecolumn)/$entity",
  "@odata.etag": "W/\"76796548\"",
  "sample_imagecolumn": "<base 64 encoded string truncated for brevity>",
  "accountid": "<accountid>"
}

This request updates the sample_imagecolumn image column with an updated image:

Request:

PATCH [Organization Uri]/api/data/v9.2/accounts(<accountid>) HTTP/1.1
If-Match: *
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json
Content-Type: application/json; charset=utf-8
Content-Length: 5220

{
  "sample_imagecolumn": "<base 64 encoded string truncated for brevity>"
}

Response:

HTTP/1.1 204 NoContent
OData-Version: 4.0
OData-EntityId: [Organization Uri]/api/data/v9.2/accounts(<accountid>)

Some libraries you may use to serialize and deserialize JSON, such as JSON.NET, will automatically convert these encoded string values to byte[] so you might not even notice that the transport protocol is using base 64 strings.

For more information, about base 64 encoded strings see:

• Base64 - MDN Web Docs Glossary
• Base64 to Image Converter
• Image to Base64 Converter

More information:

• Retrieve a table row using the Web API
• Update and delete table rows using the Web API

Simply set the value of the image attribute to null and update the entity. More information: Basic update

There are three different ways to delete an image column value using Web API.

Use PATCH and set the image column value to null

Request:

PATCH [Organization Uri]/api/data/v9.2/accounts(<accountid>) HTTP/1.1
If-Match: *
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json
Content-Type: application/json; charset=utf-8
Content-Length: 90

{
  "accountid": "<accountid>",
  "sample_imagecolumn": null
}

Response:

HTTP/1.1 204 NoContent
OData-Version: 4.0
OData-EntityId: [Organization Uri]/api/data/v9.2/accounts(<accountid>)

More information: Basic update

Use PUT and set the image column value to null

Request:

PUT [Organization Uri]/api/data/v9.2/accounts(<accountid>)/sample_imagecolumn HTTP/1.1
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json
Content-Type: application/json; charset=utf-8
Content-Length: 15

{"value": null}

Response:

HTTP/1.1 204 NoContent
OData-Version: 4.0

More information: Update a single property value

Use DELETE with the resource URL referencing the image column

Request:

DELETE [Organization Uri]/api/data/v9.2/accounts(<accountid>)/sample_imagecolumn HTTP/1.1
OData-MaxVersion: 4.0
OData-Version: 4.0
If-None-Match: null
Accept: application/json

Response:

HTTP/1.1 204 NoContent
OData-Version: 4.0

More information: Delete a single property value