> ## Documentation Index
> Fetch the complete documentation index at: https://help.dingtalk.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Cascade Select

> This document introduces the option information component with hierarchy and linkage, applicable to scenarios where you create a main category and its sub-categories, such as Department selection and city selection. The document details the basic features of the component (including showing Search, the Clear Button, and using the Data Source to Add, Delete, or modify departments) and answers frequently asked questions.

## 1. Applicable Scenarios

Option information follows a one-to-many relationship and features hierarchy and linkage. It is often used to create a main category and its sub-categories, such as Department selection and city selection (for example, province, city, and district) that involve hierarchical relationships.

<Note>
  For Component attributes, usage, and examples, [**click here**](/open/yida/components/form/cascadeSelectField).
</Note>

## 2. Basic Features

### 2.1 Show Search

Determines whether users can type Content directly in the input box to Search. When there are many Tiers, turn on the Search feature to quickly locate the target option.

Show Search

**The effect is shown below:**

### 2.2 Clear Button

Clears the Content in the option box.

Clear Button

**The effect is shown below:**

### 2.3 Use the Data Source to Add, Delete, or Modify Departments

Click Edit Code to view the Data Source of the cascade Select. Add, Delete, or modify main categories and sub-categories here.

Data Source

The structures of the first Tier and the second Tier in the Data Source are shown below:

For example, to Add a new option named "New Department" under Department > Product, follow the steps shown in figures 3 to 5:

## 3. FAQ

<AccordionGroup>
  <Accordion id="q1" title="3.1 How do I add a sub-category (a lower Tier)?">
    The final effect:
  </Accordion>

  <Accordion id="q2" title="3.2 How do I add option content?">
    The final effect:
  </Accordion>

  <Accordion id="q3" title="3.3 Why don't the Settings take effect even after I copied the Tier structure?">
    Make sure you copied the complete structure, including symbols such as `{}` and `[]`. Also check that commas are added in the correct places and that they are half-width (English) commas. If it still doesn't work, Delete the Component and Add it again.
  </Accordion>
</AccordionGroup>