feat(components): [form] FormContext adds the getField method (#14930)

* feat(components): [form] FormContext adds the getField method

* feat(components): [form-item] FormItemContext adds the fieldValue prop

* chore: update FormContext.getField return type

packages/components/form/src/form-item.vue

@@ -379,6 +379,7 @@ const context: FormItemContext = reactive({
   inputIds,
   isGroup,
   hasLabel,
+  fieldValue,
   addInputId,
   removeInputId,
   resetField,

packages/components/form/src/form.vue

@@ -48,6 +48,10 @@ const formClasses = computed(() => {
   ]
 })
 
+const getField: FormContext['getField'] = (prop) => {
+  return fields.find((field) => field.prop === prop)
+}
+
 const addField: FormContext['addField'] = (field) => {
   fields.push(field)
 }
@@ -168,6 +172,7 @@ provide(
     resetFields,
     clearValidate,
     validateField,
+    getField,
     addField,
     removeField,
 

packages/components/form/src/types.ts

@@ -113,8 +113,7 @@ export interface FormValidateFailure {
 export type FormContext = FormProps &
   UnwrapRef<FormLabelWidthContext> & {
     emit: SetupContext<FormEmits>['emit']
-
-    // expose
+    getField: (prop: string) => FormItemContext | undefined
     addField: (field: FormItemContext) => void
     removeField: (field: FormItemContext) => void
     resetFields: (props?: Arrayable<FormItemProp>) => void
@@ -133,6 +132,7 @@ export interface FormItemContext extends FormItemProps {
   labelId: string
   inputIds: string[]
   hasLabel: boolean
+  fieldValue: any
   addInputId: (id: string) => void
   removeInputId: (id: string) => void
   validate: (