element table input 框 數據 默認選中

<el-table
          ref="table"
          :data="url_data.cart"
          class="content-row table_scroll"
          row-key="id"
          default-expand-all
          :tree-props="{children: 'mz', hasChildren: 'hasChildren'}"
          fixed
          @selection-change="changFun"
        >
          <el-table-column width="60">
            **<template slot-scope="scope">
              <el-checkbox
                v-if="scope.row.is_must != null"
                :disabled="scope.row.is_must == 1"
                v-model="send_checked[scope.$index]"
              > <span style="color:#c39a58">贈</span> </el-checkbox>
            </template>**
          </el-table-column>

data{
	 send_checked: [],
      table_all_data: []
}

數據調用
 this.url_data = res.data.data;
            this.url_data.cart.forEach(element => {
              this.table_all_data.push(element);
              if (element.mz != null) {
                element.mz.forEach(item => {
                  item.ware_id = { ware_id: element.ware_id.ware_id };
                  item.pid = element.good_itemid;
                  this.table_all_data.push(item);
                });
              }
            });
            this.table_all_data.forEach((item, index) => {
              if (item.is_must == 1) {
                this.send_checked[index] = true;
              } else {
                this.send_checked[index] = false;
              }
            });