how to save data in database using JSON file in angular

Question

Hii I am trying to save my HTML form data in the database. I create a JSON file for Dynamic fields and I bind it but there is some problem that's why data is not save. When I save the data, the same data is saved as it is in the JSON file as if I entered some string value in the input field, it is not saved but the original string is the same.

 <div>
                        <p *ngFor="let item of doclist">
                            {{ item.label }}
                            <ejs-checkbox [(ngModel)]="item.value" id="item.value"  name="item.value">
                                {{ item.value }}
                            </ejs-checkbox>
                            <ejs-textbox *ngIf="item.value == true && !false"[(ngModel)]="item.comment" 
name="item.comment">
                                {{ item.comment }}
                            </ejs-textbox>
                        </p>
                    </div>

  public doclist : {}[] = db;
  public doc = JSON.stringify(this.doclist);
  this.salesToOpsHand.documentList = this.doc;
`// documentList in that i have to save my all json string value so i write here doc values  == documentList`

this is my db.json file

[
  {
  "name" : "IsSpecifications",
  "label" : "isSpecifications() ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "IsDrawSchedule",
  "label" : "Drawings/Schedules ",
  "value" : false,
  "type" : "checkbox",

  "comment" : ""
  },
  {
  "name" : "TqRfi",
  "label" : "TQ’s / RFI’s ",
  "value" : false,
  "type" : "checkbox",

  "comment" : ""
  },
  {
  "name" : "InsEnqReqQouInfor",
  "label" : "Install Enquiry / request to quote information ",
  "value" : false,
  "type" : "checkbox",

  "comment" : ""
  },
  {
  "name" : "PanEnqReqQouInfor",
  "label" : "Panel Enquiry / request to quote information ",
  "value" : false,
  "type" : "checkbox",

  "comment" : ""
  },
  {
  "name" : "PanSubContQuot",
  "label" : "Panel Sub Contractor Quotation ",
  "value" : false,
  "type" : "checkbox",

  "comment" : ""
  },
  {
  "name" : "MccSchedule",
  "label" : "MCC Schedules ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "ScPackQuot",
  "label" : "Other S/C Package Quotations ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "OthrdPartyQuot",
  "label" : "Other 3rd Party Quotations ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "EquipSchedule",
  "label" : "Equipment Schedules ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "PointSchedul",
  "label" : "Points Schedules ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "ValveSchedul",
  "label" : "Valve Schedules ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "IdentRiskOpport",
  "label" : "Identifed Risks and Opportunities (INCL. VALUE ENGINEERING) ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  },
  {
  "name" : "InstSubContQuot",
  "label" : "Install Sub Contractor Quotation ",
  "value" : false,
  "type" : "checkbox",
  "comment" : ""
  }
]

`if someone knows where is am doing a mistake please help me

here I try angular and JSON file and save the value in form of a string in the server side`