diff --git a/backed/internal/service/cpdaily/leave_xsgz.go b/backed/internal/service/cpdaily/leave_xsgz.go
index 2fdbe25..5382550 100644
--- a/backed/internal/service/cpdaily/leave_xsgz.go
+++ b/backed/internal/service/cpdaily/leave_xsgz.go
@@ -416,13 +416,40 @@ func xsgzFlatten(prefix string, v interface{}, out *[][2]string) {
 			xsgzFlatten(key, child, out)
 		}
 	case []interface{}:
-		// 数组下标用方括号，对象键用点号——这是前端源码的硬编码行为：
-		//   studentForm-Dx5Fpjfs.js:
-		//     function pe(e,t,a){return e?a?`${e}[${t}]`:`${e}.${t}`:t}
-		//     v(): s.forEach((l,p)=>{const c=`${i}[${p}]`; ... })
-		//   调用方 LeaveApplyDrawer: le(T, D.value) → Ne(e,t={},a=false) → v(...,a=false)
-		// 即使 a=false（对象键走点号），数组下标依然固定为 [n]。
-		// 实际提交形如：fields[0].fieldId / fields[0].value / fields[1].value
+		// 前端 v() 对数组分两种情况（studentForm-Dx5Fpjfs.js）：
+		//   if (s.some(l => l && typeof l == "object")) → 按下标展开 `${i}[${p}]`
+		//   else → const l = s.map(p => p ?? "").join(","); append(i, l)
+		// 即「含对象」才用方括号下标，「纯原始值数组」要拼成逗号串单键。
+		// 键名规则本身仍是：对象键点号、数组下标方括号
+		// （pe(e,t,a) 里的 a 只影响对象键，与数组分支无关）。
+		hasObject := false
+		for _, el := range val {
+			if _, ok := el.(map[string]interface{}); ok {
+				hasObject = true
+				break
+			}
+		}
+		if !hasObject {
+			// 纯原始值：拼成 "a,b,c"，只提交一个键
+			if len(val) == 0 {
+				return // 空数组：前端 join 得 ""，我们不提交空值
+			}
+			parts := make([]string, 0, len(val))
+			for _, el := range val {
+				if el == nil {
+					parts = append(parts, "") // JS: p ?? ""
+					continue
+				}
+				parts = append(parts, fmt.Sprintf("%v", el))
+			}
+			joined := strings.Join(parts, ",")
+			if joined == "" {
+				return // 全空，不提交
+			}
+			*out = append(*out, [2]string{prefix, joined})
+			return
+		}
+		// 含对象：按下标逐个展开
 		for i, child := range val {
 			key := fmt.Sprintf("%s[%d]", prefix, i)
 			xsgzFlatten(key, child, out)
diff --git a/backed/internal/service/cpdaily/leave_xsgz_jsref_test.go b/backed/internal/service/cpdaily/leave_xsgz_jsref_test.go
new file mode 100644
index 0000000..f3a18c6
--- /dev/null
+++ b/backed/internal/service/cpdaily/leave_xsgz_jsref_test.go
@@ -0,0 +1,254 @@
+package cpdaily
+
+import (
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// 把前端 studentForm-Dx5Fpjfs.js 的 v()/pe() 忠实转写成参考实现，
+// 用它对拍 xsgzFlatten，避免再靠肉眼推断契约细节。
+//
+// 原文：
+//
+//	function pe(e,t,a){return e?a?`${e}[${t}]`:`${e}.${t}`:t}
+//	function v(e,t,a,o=false){
+//	  const r=t||new FormData
+//	  for(const n in e){
+//	    if(!Object.prototype.hasOwnProperty.call(e,n))continue
+//	    const s=e[n]
+//	    if(s===void 0)continue
+//	    const i=pe(a,n,o)
+//	    if(s instanceof Date) r.append(i,s.toISOString())
+//	    else if(Array.isArray(s))
+//	      if(s.some(l=>l&&typeof l=="object"))
+//	        s.forEach((l,p)=>{const c=`${i}[${p}]`
+//	          if(l&&typeof l=="object"){ if(l.status==="done")return
+//	            "file"in l&&(l.file instanceof File||l.file instanceof Blob)
+//	              ? r.append(o?`${c}[file]`:`${c}.file`,l.file,...)
+//	              : v(l,r,c,o) }
+//	          else r.append(c,l??""); })
+//	      else { const l=s.map(p=>p??"").join(","); r.append(i,l) }
+//	    else typeof s=="object"&&!(s instanceof File) ? v(s,r,i,o)
+//	    : r.append(i,s??"")
+//	  }
+//	  return r
+//	}
+
+// jsPe 对应 pe(e,t,a=false)：对象键用点号。
+func jsPe(prefix, key string) string {
+	if prefix == "" {
+		return key
+	}
+	return prefix + "." + key
+}
+
+// jsFlatten 对应 v()，返回前端会写入 FormData 的键值对。
+func jsFlatten(prefix string, v interface{}, out *[][2]string) {
+	switch val := v.(type) {
+	case nil:
+		// JS: null 不是 undefined，会 append(key, null ?? "") 即空串
+		*out = append(*out, [2]string{prefix, ""})
+	case map[string]interface{}:
+		for k, child := range val {
+			jsFlatten(jsPe(prefix, k), child, out)
+		}
+	case []interface{}:
+		hasObject := false
+		for _, el := range val {
+			if _, ok := el.(map[string]interface{}); ok {
+				hasObject = true
+				break
+			}
+		}
+		if hasObject {
+			// 含对象 → 按下标逐个展开
+			for i, child := range val {
+				key := fmt.Sprintf("%s[%d]", prefix, i)
+				if _, ok := child.(map[string]interface{}); ok {
+					jsFlatten(key, child, out)
+				} else {
+					*out = append(*out, [2]string{key, jsScalar(child)})
+				}
+			}
+			return
+		}
+		// 全是原始值 → join(",") 成单个键（关键差异点）
+		parts := make([]string, 0, len(val))
+		for _, el := range val {
+			parts = append(parts, jsScalar(el))
+		}
+		*out = append(*out, [2]string{prefix, strings.Join(parts, ",")})
+	case string:
+		*out = append(*out, [2]string{prefix, val})
+	case bool:
+		*out = append(*out, [2]string{prefix, strconv.FormatBool(val)})
+	default:
+		*out = append(*out, [2]string{prefix, fmt.Sprintf("%v", val)})
+	}
+}
+
+// jsScalar 对应 JS 的 `l ?? ""` 加隐式字符串化。
+func jsScalar(v interface{}) string {
+	if v == nil {
+		return ""
+	}
+	return fmt.Sprintf("%v", v)
+}
+
+// toMap 把键值对转成 map，便于比较。
+func toMap(pairs [][2]string) map[string]string {
+	m := map[string]string{}
+	for _, kv := range pairs {
+		m[kv[0]] = kv[1]
+	}
+	return m
+}
+
+// compareFlatten 对拍：对前端产出的每个非空键值，断言 Go 实现一致。
+//
+// 已知并有意的差异：前端会以空字符串提交（null → ""），我们跳过空值。
+// 对表单提交而言两者对必填校验等价，且跳过更干净，故此处不追究空值键。
+func compareFlatten(t *testing.T, name string, payload map[string]interface{}) {
+	t.Helper()
+
+	var jsPairs, goPairs [][2]string
+	jsFlatten("", payload, &jsPairs)
+	xsgzFlatten("", payload, &goPairs)
+
+	js := toMap(jsPairs)
+	got := toMap(goPairs)
+
+	for k, want := range js {
+		if want == "" {
+			continue // 有意差异：我们不提交空值
+		}
+		if gotVal, ok := got[k]; !ok {
+			t.Errorf("%s: 缺少键 %q（前端提交 %q）", name, k, want)
+		} else if gotVal != want {
+			t.Errorf("%s: 键 %q 值不一致 got=%q want=%q", name, k, gotVal, want)
+		}
+	}
+	// 反向：我们不应多提交前端没有的键
+	for k, v := range got {
+		if v == "" {
+			continue
+		}
+		if _, ok := js[k]; !ok {
+			t.Errorf("%s: 多出键 %q=%q（前端无此键）", name, k, v)
+		}
+	}
+}
+
+// TestXsgzFlattenMatchesFrontend 用真实形态的载荷对拍前后端序列化。
+func TestXsgzFlattenMatchesFrontend(t *testing.T) {
+	cases := []struct {
+		name    string
+		payload map[string]interface{}
+	}{
+		{
+			name: "请假提交（字段含 options 数组）",
+			payload: map[string]interface{}{
+				"projectId":   "proj-1",
+				"requestType": "LEAVE",
+				"startTime":   "2026-10-17 08:00:00",
+				"endTime":     "2026-10-18 18:00:00",
+				"address":     "山东农业大学",
+				"longitude":   "117.12",
+				"latitude":    "36.19",
+				"fields": []interface{}{
+					map[string]interface{}{
+						"fieldId": "f1", "fieldName": "请假原因",
+						"componentType": "TEXT", "fieldType": "TEXT",
+						"required": true, "value": "感冒",
+						"options": []interface{}{
+							map[string]interface{}{"label": "是", "value": "1"},
+							map[string]interface{}{"label": "否", "value": "0"},
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "销假提交（含布尔与 originalId）",
+			payload: map[string]interface{}{
+				"originalId":              "apply-99",
+				"projectId":               "proj-2",
+				"requestType":             "CANCELLATION",
+				"inArea":                  true,
+				"cancellationApplyInArea": false,
+				"fields": []interface{}{
+					map[string]interface{}{"fieldId": "c1", "value": "已返校"},
+				},
+			},
+		},
+		{
+			name: "多字段多类型",
+			payload: map[string]interface{}{
+				"projectId": "p",
+				"fields": []interface{}{
+					map[string]interface{}{"fieldId": "a", "value": "文本"},
+					map[string]interface{}{"fieldId": "b", "value": "x,y"},
+					map[string]interface{}{"fieldId": "c", "value": "true"},
+				},
+			},
+		},
+		{
+			name: "空 fields 数组",
+			payload: map[string]interface{}{
+				"projectId": "p",
+				"fields":    []interface{}{},
+			},
+		},
+		{
+			name: "嵌套 map",
+			payload: map[string]interface{}{
+				"projectId": "p",
+				"applicant": map[string]interface{}{
+					"xgh": "202412303232", "xm": "张三",
+				},
+			},
+		},
+	}
+
+	for _, c := range cases {
+		compareFlatten(t, c.name, c.payload)
+	}
+}
+
+// TestXsgzFlattenArrayOfPrimitives 单列数组规则：前端 join(",")，我们此前按下标。
+func TestXsgzFlattenArrayOfPrimitives(t *testing.T) {
+	payload := map[string]interface{}{
+		"tags": []interface{}{"a", "b", "c"},
+	}
+	var jsPairs [][2]string
+	jsFlatten("", payload, &jsPairs)
+	js := toMap(jsPairs)
+	t.Logf("前端产出: %v", js)
+
+	var goPairs [][2]string
+	xsgzFlatten("", payload, &goPairs)
+	got := toMap(goPairs)
+	t.Logf("Go 产出:  %v", got)
+
+	// 前端是一个键 tags="a,b,c"
+	if js["tags"] != "a,b,c" {
+		t.Fatalf("参考实现异常: %v", js)
+	}
+	if got["tags"] != "a,b,c" {
+		t.Errorf("原始值数组应 join 成单键 tags=a,b,c，实际 %v", got)
+	}
+	// 不应出现索引键
+	keys := make([]string, 0, len(got))
+	for k := range got {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		if strings.HasPrefix(k, "tags[") {
+			t.Errorf("不应出现索引键 %q（前端会 join）", k)
+		}
+	}
+}