<el-col :span="4">
    <el-form-item label="代理商">
        <el-select v-model="formData.agentid" placeholder="" @change="changeAgent">
            <el-option label="全部" :value="0"></el-option>
            <el-option :label="item.agentname" :value="item.agentid" :key="item.agentid"
                       v-for="item in dlsList"></el-option>
        </el-select>
    </el-form-item>
</el-col>
<el-col :span="4">
    <el-form-item label="工作室">
        <el-select v-model="formData.studioid" placeholder="">
            <el-option label="无" :value="0"></el-option>
            <el-option :label="item.studioname" :value="item.studioid" :key="item.studioid"
                       v-for="item in gzsList" v-if="formData.agentid == item.agentid"></el-option>
        </el-select>
    </el-form-item>
</el-col>
<el-col :span="4">
    <el-form-item label="销售">
        <el-select v-model="formData.sellerid" placeholder="">
            <el-option label="无" :value="0"></el-option>
            <el-option :label="item.sellername" :value="item.sellerid" :key="item.sellerid"
                       v-for="item in xsList" v-if="formData.studioid == item.studioid"></el-option>
        </el-select>
    </el-form-item>
</el-col>

通过3级联动关联信息控制option显示