update

app/adminapi/lists/cost_project/CostProjectLists.php

@@ -58,6 +58,7 @@ class CostProjectLists extends BaseAdminDataLists implements ListsSearchInterfac
         return CostProject::where($this->searchWhere)
             ->field(['id', 'project_num', 'project_name', 'contract_id', 'types', 'industry', 'province', 'city', 'address', 'starting', 'endtime', 'jhgq', 'depar', 'principal', 'person', 'invest', 'budget', 'cost', 'approval', 'aunit', 'Acontact', 'acontactnum', 'date', 'generalize', 'note', 'remark', 'annex'])
             ->limit($this->limitOffset, $this->limitLength)
+            ->with(['contract'])
             ->order(['id' => 'desc'])
             ->select()
             ->toArray();

app/common/model/cost_project/CostProject.php

@@ -30,5 +30,8 @@ class CostProject extends BaseModel
     protected $name = 'cost_project';
     protected $deleteTime = 'delete_time';
 
-    
+    public function contract()
+    {
+        return $this->hasOne(CostApprovedProject::class, 'id','contract_id');
+    }
 }