From 4609d218655609f565bfd17d6bfe3ab435bb2179 Mon Sep 17 00:00:00 2001
From: zhangxCode <zhangxiong076@chinasoftinc.com>
Date: Wed, 4 Jun 2025 10:49:03 +0800
Subject: [PATCH] =?UTF-8?q?FAQ=EF=BC=9A=E6=96=B0=E5=A2=9E=E4=BB=A3?=
 =?UTF-8?q?=E7=A0=81=E5=90=8C=E6=BA=90?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../main/ets/pages/ArktsTypeConversion.ets    | 34 +++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)

diff --git a/ArkUI/entry/src/main/ets/pages/ArktsTypeConversion.ets b/ArkUI/entry/src/main/ets/pages/ArktsTypeConversion.ets
index fe97c5b..caa093d 100644
--- a/ArkUI/entry/src/main/ets/pages/ArktsTypeConversion.ets
+++ b/ArkUI/entry/src/main/ets/pages/ArktsTypeConversion.ets
@@ -2,7 +2,7 @@
  * FAQ:ArkTS类型转换方法，除了使用as是否有其他方法
  */
 class TargetClass {
-  someProperty: string = '';
+  someProperty?: string;
   someMethod: () => void = () => {
   };
 }
@@ -21,6 +21,20 @@ function testFn(anyObject: TargetClass) {
 
 const anyObject = new TargetClass();
 
+// [Start type_is]
+function isTargetClass(obj: object) {
+  return obj instanceof TargetClass && obj.someProperty === 'expectedValue';
+}
+
+if (isTargetClass(anyObject)) {
+  // Now it is safe to use anyObject as an instance of Target Class
+} else {
+  // Dealing with objects that do not conform to the Target Class
+}
+
+// [End type_is]
+
+
 // [Start type_as]
 function testFn2(anyObject: TargetClass) {
   try {
@@ -31,4 +45,20 @@ function testFn2(anyObject: TargetClass) {
     // Dealing with situations where type conversion fails or method calls are incorrect
   }
 }
-// [End type_as]
\ No newline at end of file
+
+// [End type_as]
+
+// [Start type_asserts]
+function assertIsTargetClass(obj: object) {
+  if (!(obj instanceof TargetClass)) {
+    throw new Error('Object is not an instance of TargetClass');
+  }
+}
+
+try {
+  assertIsTargetClass(anyObject);
+  // Now it is safe to use anyObject as an instance of Target Class
+} catch (error) {
+  // Failure to handle type assertion
+}
+// [End type_asserts]
\ No newline at end of file
-- 
Gitee