---
alias: user-guide-business-workflow-task-map-collection
render_macros: false
description: "Projects supplied entities or records into fresh scalar-valued records without changing source objects."
---

# Map Collection Fields

Projects supplied entities or records into fresh scalar-valued records without changing source objects.

![Screenshot of a Business Workflow projecting Material fields with a supplied mapping collection.](images/business-workflow-task-map-collection.png)

## Inputs

Set `Collection`, `Mappings` in the task details. Use the value editor to select compatible results from earlier tasks.

`Mappings` accepts a collection of `Cmf.Foundation.BusinessObjects.Tasks.MapCollectionTask.FieldMapping` objects. Enter a C# expression enclosed in `{{ ... }}` directly in this input, or reference an earlier output containing that type.

| Property | Description |
| --- | --- |
| `Name` | Required output field name. Names must be unique, ignoring case. |
| `Source` | Dot-separated field path relative to the current item. Leave it unset to use `Value`. |
| `Value` | Scalar constant or earlier result to use when `Source` is unset. |
| `ValueType` | Logical scalar type, such as `String` or `Decimal`. The default, `Object`, preserves the scalar's type. |
| `DefaultValue` | Fallback for a missing source path. A present null value remains null. |

Table 1: Field mapping properties

## Outputs

Use `Rows`, `RowCount` in subsequent tasks.

??? example "Project Material Names and Quantities"

    Use a preceding [Load or Refresh Entities](../entities/business-workflow-task-load-entities.md) task named `load` to load the **Materials** to project.

    1. Add **Map Collection Fields** after `load` and name it `map`.
    2. Set `Collection` to `{{$load.Result}}`.
    3. Enter the following expression in `Mappings`:

        ```csharp
        {{new Cmf.Foundation.BusinessObjects.Tasks.MapCollectionTask.FieldMapping[] {
            new() { Name = "LotName", Source = "Name", ValueType = "String" },
            new() { Name = "Quantity", Source = "PrimaryQuantity", ValueType = "Decimal" }
        }}}
        ```

    4. Use `{{$map.Rows}}` in a subsequent task, such as **Compose JSON**. Each record contains `LotName` and `Quantity`; the original **Materials** remain unchanged.

## Behavior

Connect a compatible collection of field mappings to `Mappings`. The task creates new records and leaves the source collection unchanged. A field mapping identifies its output name, source field or constant value, and value type.