first commit

app/users/[userId]/useEffect-demo.tsx

@@ -0,0 +1,37 @@
+"use client";
+
+import { useState, useEffect } from "react";
+
+const UseEffectBasics = () => {
+  const [value, setValue] = useState(0);
+
+  const handleClick = () => {
+    setValue(value + 1);
+  };
+
+  const sayHello = () => {
+    console.log("hello there");
+  };
+
+  useEffect(() => {
+    sayHello();
+  });
+
+  // useEffect(() => {
+  //   sayHello();
+  // }, []);
+
+  // useEffect(() => {
+  //   sayHello();
+  // }, [value]);
+
+  return (
+    <div className="card w-96 bg-base-100 shadow-xl border border-base-200">
+      <h1>value : {value}</h1>
+      <button className="btn" onClick={handleClick}>
+        click me
+      </button>
+    </div>
+  );
+};
+export default UseEffectBasics;