合并FormGroups

Question

你好，我有一个关于formGroups或abstractControls的一般问题

我通过FormBuilder创建我的FormGroup

createControl() {
 const group = this.fb.group({});
 this.fields.forEach(field => {
   if (field.type === 'button') {
     return;
   }
   const control = this.fb.control(
     {value: field.value, disabled: field.disabled},
     this.bindValidations(field.validations || [])
   );
   group.addControl(field.name, control);
 });
 return group;
}

当我想要创建动态表单时，我会使用表单生成器。现在一些值发生了变化，some控件的一些选项也发生了变化。我的服务器向我发送了一个新的FormGroup表示。是否可以通过表单生成器创建一个新表单，并将其与我的旧表单组合并？

从服务器响应

{"formControls[
  {"name":"name","inputType":"text","disabled":false,"label":"Username","type":"input"},
  {"name":"gender","options":["Male","Female"],"label":"Gender","type":"radiobutton","value":"Male"},
  {"name":"country","options":
    [{"value":"Germany","key":"1"},{"value":"Germany","key":"2"}],
    "disabled":false,"label":"Country","type":"select","value":"UK"}],"name":"MyFirstForm"}

Answer 1

稍微修改一下你的函数createControl

createControl(groupOld) {
   //then you can
   const group = groupOld|| this.fb.group({});
   ....and add all the fields of this.fields..
   ..you can use a if like
   if (!groupOld.get('field.value'))
       //add the field

   //or 
   const value=groupOld.value
   ...and after create the form use 
   group.patchVallue(value);
}