EasyExcel Dynamic Columns Export【Sample Code】Implementation of Dynamic Columns, Supporting Extension of Original Entity Class Annotations

# 1. Introduction

### Background Introduction

Exporting Excel is a common need in actual development, but when it comes to dynamic column export, traditional methods may fall short. This article will introduce how to use EasyExcel, an excellent open-source library, to implement dynamic column export functionality.

### EasyExcel Overview

EasyExcel is an open-source Excel parsing and generation tool developed by Alibaba. Its advantages lie in high performance, low memory consumption, and ease of use. With EasyExcel, developers can easily manipulate Excel files and implement import/export等功能.

### Demand and Challenges of Dynamic Column Export

Dynamic column export refers to the creation of Excel tables based on dynamic fields, a need that arises in many scenarios, such as exporting custom field reports or exporting different fields based on user permissions. The challenge of implementing dynamic column export lies in dynamically generating Excel without prior knowledge of the number of columns and their content. The EasyExcel library provides a simple and efficient solution.

# 2. **Dynamic Column Export Implementation Technical Analysis**

- The principle of using EasyExcel to implement dynamic column export
- The significance and function of extending annotations on the original entity class
- Analysis of example code

# 3. **Detailed Steps for Dynamic Column Export Implementation**

In this section, we will delve into the steps to implement dynamic column export, including preparation work, implementation process, and interpretation of key code.

#### **Preparation Work: Importing Dependencies and Configuration**

Before implementing dynamic column export, it's essential to ensure that the project has imported the necessary dependency libraries, such as EasyExcel. Project configuration files also need to be set with relevant parameters to support the implementation of dynamic column export.

#### **Steps for Dynamic Column Export Implementation**

1. Build the export data collection: Dynamically generate or filter the data collection for export based on business requirements, including dynamic column data.

2. Create Excel headers: Dynamically generate corresponding Excel headers based on the information of dynamic columns in the data collection.

3. Configure export parameters: Set relevant parameters for Excel export, such as file name, export path, etc.

4. Perform data filling: Fill the data from the data collection into the corresponding Excel table, including dynamic column data.

5. Execute the export operation: Call the export method provided by EasyExcel to export the filled Excel table to a specified path.

#### **Detailed Explanation of Key Code for Dynamic Column Export Implementation**

Below is a simple Java code snippet that demonstrates how to use EasyExcel to implement the key parts of dynamic column export:

// Build export data collection
List<ExportData> dataList = getDataForExport();