go get github.com/gin-gonic/gin
go get github.com/mojocn/base64Captcha

package main

import (
	"github.com/gin-gonic/gin"
	"github.com/mojocn/base64Captcha"
	"net/http"
)

// 驗(yàn)證碼存儲(chǔ)在內(nèi)存中（也可以換成 Redis）
var store = base64Captcha.DefaultMemStore

// 生成驗(yàn)證碼
func generateCaptcha(c *gin.Context) {
	driver := base64Captcha.NewDriverDigit(80, 240, 5, 0.7, 80) // 高度80, 寬度240, 5位數(shù)字
	captcha := base64Captcha.NewCaptcha(driver, store)
	id, b64s, err := captcha.Generate()
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "驗(yàn)證碼生成失敗"})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"captcha_id":   id,
		"captcha_image": b64s, // Base64 編碼的圖片
	})
}

// 校驗(yàn)驗(yàn)證碼
func verifyCaptcha(c *gin.Context) {
	var req struct {
		ID    string `json:"id"`
		Value string `json:"value"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	if store.Verify(req.ID, req.Value, true) { // true 表示驗(yàn)證成功后清除
		c.JSON(http.StatusOK, gin.H{"message": "驗(yàn)證成功"})
	} else {
		c.JSON(http.StatusBadRequest, gin.H{"message": "驗(yàn)證碼錯(cuò)誤"})
	}
}

func main() {
	r := gin.Default()
	r.GET("/captcha", generateCaptcha)
	r.POST("/verify", verifyCaptcha)
	r.Run(":8080")
}

go run main.go

curl http://localhost:8080/captcha

{
  "captcha_id": "ZffX7Xr7EccGdS4b",
  "captcha_image": "data:image/png;base64,iVBORw0KGgoAAAANSUhE..."
}

curl -X POST http://localhost:8080/verify \
  -H "Content-Type: application/json" \
  -d '{"id":"ZffX7Xr7EccGdS4b","value":"12345"}'