Vue reports error in render: “typeerror: cannot read property ‘length’ of undefined“
Reason: there is undefined in the (list) attribute of El table, and all columns can be judged by adding a V-IF
<el-table-column label="数据库" width="500px"> <template slot="header"> <el-button @click="counterElection('主键', 'sqlOpt')" size="small" type="default" >主键 </el-button> <el-button @click="counterElection('非空', 'sqlOpt')" size="small" type="default" >非空 </el-button> <el-button @click="counterElection('唯一', 'sqlOpt')" size="small" type="default" >唯一 </el-button> <el-button @click="counterElection('索引', 'sqlOpt')" size="small" type="default" >索引 </el-button> <el-button @click="counterElection('忽略', 'sqlOpt')" size="small" type="default" >忽略 </el-button> <el-button @click="counterElection('自增', 'sqlOpt')" size="small" type="default" >自增 </el-button> </template> <template slot-scope="scope"> <el-checkbox-group v-if=" scope.row !== undefined && scope.row.sqlOpt !== undefined " v-model="scope.row.sqlOpt" > <el-checkbox label="主键"></el-checkbox> <el-checkbox label="非空"></el-checkbox> <el-checkbox label="唯一"></el-checkbox> <el-checkbox label="索引"></el-checkbox> <el-checkbox label="忽略"></el-checkbox> <el-checkbox label="自增"></el-checkbox> </el-checkbox-group> </template> </el-table-column>