在 UI 中进行映射

¥Mapping in the UI

数据映射是指引用来自先前节点的数据。它不包含更改（转换）数据的操作，仅包含引用操作。

¥Data mapping means referencing data from previous nodes. It doesn't include changing (transforming) data, just referencing it.

你可以通过以下方式映射数据：

¥You can map data in the following ways:

• 使用表达式编辑器。

¥Using the expressions editor.

• 通过将数据从输入节点拖放到参数中。这将为你生成表达式。

¥By dragging and dropping data from the INPUT into parameters. This generates the expression for you.

有关映射和链接项时出现的错误信息，请参阅 项目链接错误。

¥For information on errors with mapping and linking items, refer to Item linking errors.

如何拖放数据

¥How to drag and drop data

1. 运行你的工作流以加载数据。

¥Run your workflow to load data. 2. 打开需要映射数据的节点。

¥Open the node where you need to map data. 3. 你可以在表格、JSON 和模式视图中进行映射：

¥You can map in table, JSON, and schema view:

• 表格视图：单击并按住表格标题以映射顶层数据，或单击并按住表格中的字段以映射嵌套数据。

  ¥In table view: click and hold a table heading to map top level data, or a field in the table to map nested data.

• 在 JSON 视图中：单击并按住某个键。

  ¥In JSON view: click and hold a key.

• 架构视图：单击并按住某个键。

  ¥In schema view: click and hold a key. 4. 将项目拖到要使用数据的字段中。

¥Drag the item into the field where you want to use the data.

理解拖放映射的内容删除

¥Understand what you're mapping with drag and drop

数据映射映射键路径，并将键的值加载到字段中。例如，给定以下数据：

¥Data mapping maps the key path, and loads the key's value into the field. For example, given the following data:

[
	{
		"fruit": "apples",
		"color": "green"
	}
]

你可以将水果从输入框拖放到你想要使用其值的字段中，从而映射 fruit。此教程将创建一个表达式 {{ $json.fruit }}。当节点遍历输入项时，每个项的字段值都会变为 fruit 的值。

¥You can map fruit by dragging and dropping fruit from the INPUT into the field where you want to use its value. This creates an expression, {{ $json.fruit }}. When the node iterates over input items, the value of the field becomes the value of fruit for each item.

理解嵌套数据

¥Understand nested data

给定以下数据：

¥Given the following data:

[
  {
    "name": "First item",
    "nested": {
      "example-number-field": 1,
      "example-string-field": "apples"
    }
  },
  {
    "name": "Second item",
    "nested": {
      "example-number-field": 2,
      "example-string-field": "oranges"
    }
  }
]

n8n 以表格形式显示如下内容：

¥n8n displays it in table form like this: