教学伴奏，声部选择可以为，为空则为所有声部

src/views/accompaniment/modals/form.vue

@@ -89,8 +89,8 @@
             <el-form-item
               :prop="`sysMusicScoreAccompaniments.${index}.subjectId`"
               label="声部"
-              :rules="[{required: true, message: '请选择声部'}]"
             >
+            <!-- :rules="[{required: true, message: '请选择声部'}]" -->
               <el-select style="width: 100%!important;" v-model="song.subjectId" placeholder="请选择声部">
                 <el-option
                   v-for="item in selects.subjects"
@@ -216,7 +216,7 @@ export default {
     await this.FetchTree()
     await this.memberRank()
     if (this.detail) {
-      console.log(this.detail)
+      // console.log(this.detail)
       this.$set(this.form, 'sysMusicScore', {
         name: this.detail.name,
         url: this.detail.url,
@@ -281,7 +281,13 @@ export default {
         const res = await queryPageSysExam({
           sysMusicScoreId: this.detail.id
         })
-        this.$set(this.form, 'sysMusicScoreAccompaniments', res.data)
+        const result = res.data || []
+        result.forEach(item => {
+          if(!item.subjectId) {
+            item.subjectId = null
+          }
+        })
+        this.$set(this.form, 'sysMusicScoreAccompaniments', result)
       } catch (error) {}
     },
     createSys() {