golang解析cad的dxf文件

DXF 是 Drawing Exchange Format或Drawing Interchange Format的简称，是AutoCAD支持的开放数据文件格式。
http://docs.autodesk.com/ACD/2011/CHS/filesDXF/WS1a9193826455f5ff18cb41610ec0a2e719-7a3d.htm

CAD 作图

1. 画一个矩形，在矩形中画一个圆，选中后定义为一个块
   
2. 保存为dxf文件，格式使用AutoCAD R12/LT2 DXF
   

示例代码

golang 包
github.com/rpaloschi/dxf-go

/*
 * @Date: 2022-06-19 15:47:08
 * @LastEditors: Jason Chen
 * @LastEditTime: 2022-07-02 18:49:10
 */

package controller

import (
    "fmt"
    "log"
    "os"
    "testing"

    // document package
    "github.com/rpaloschi/dxf-go/document"
    // entities package
    "github.com/rpaloschi/dxf-go/entities"
  
    "github.com/axgle/mahonia"
)

func Test_Parse(t *testing.T) {
    dxfPath := "smaple.dxf"
    file, err := os.Open(dxfPath)
    if err != nil {
        log.Fatal(err)
    }

    doc, err := document.DxfDocumentFromStream(file)
    if err != nil {
        log.Fatal(err)
    }

    for _, block := range doc.Blocks {
        for _, entity := range block.Entities {
            if polyline, ok := entity.(*entities.Polyline); ok {
                fmt.Println("polyline: ")
                for index, item := range polyline.Vertices {
                    fmt.Printf("[%v] (%v, %v) \n", index, item.Location.X, item.Location.Y)
                }
                // process polyline here...
            } else if line, ok := entity.(*entities.Line); ok {
                msg := fmt.Sprintf("line: start（%v），end（%v）", line.Start, line.End)
                fmt.Println(msg)
            } else if lwpolyline, ok := entity.(*entities.LWPolyline); ok {
                fmt.Println(lwpolyline)
                // process lwpolyline here...
            } else if circle, ok := entity.(*entities.Circle); ok {
                msg := fmt.Sprintf("circle: 圆心（%v），半径（%v）", circle.Center, circle.Radius)
                fmt.Println(msg)
            } else if text, ok := entity.(*entities.Text); ok {
                fmt.Println("text: " + ConvertToString(text.Value, "gbk", "utf-8"))
            }
            //...
        }
    }

}

// 字符转码
// e.g. 中文字符乱码问题 ConvertToString(str1, "gbk", "utf-8")
func ConvertToString(src string, srcCode string, tagCode string) string {
    srcCoder := mahonia.NewDecoder(srcCode)
    srcResult := srcCoder.ConvertString(src)
    tagCoder := mahonia.NewDecoder(tagCode)
    _, cdata, _ := tagCoder.Translate([]byte(srcResult), true)
    result := string(cdata)
    return result
}