效果

封装后的组件

 <template>
  <el-dialog v-model="dialogVisible" :show-close="false" :fullscreen="fullscreen" draggable overflow>
    <template #header="{ close }">
      <div>
        <span style="font-weight: bolder">{{ title0 }}</span>
        <el-icon style="cursor: pointer; float: right" @click="close"><Close /></el-icon>
        <el-icon style="cursor: pointer; float: right; margin-right: 8px" @click="fullScreenFun"><FullScreen /></el-icon>
        <el-icon style="cursor: pointer; float: right; margin-right: 8px" @click="close"><Minus /></el-icon>
      </div>
    </template>
    <slot>默认内容</slot>

    <template #footer>
      <el-button @click="dialogVisible = false">取消</el-button>
      <el-button type="primary" @click="submit"> 确定 </el-button>
    </template>
  </el-dialog>
</template>

<script setup lang="tsx" name="assignRoleDialog">
import { ref } from "vue";
// 标题
const title0 = ref("默认标题");
//弹窗是否显示
const dialogVisible = ref(false);
//是否全屏
const fullscreen = ref(false);

//打开对话框
const openDialog = (title: string) => {
  title0.value = title;
  dialogVisible.value = true;
};
//关闭对话框
const closeDilog = () => {
  dialogVisible.value = false;
};

const fullScreenFun = () => {
  fullscreen.value = !fullscreen.value;
};

const emits = defineEmits(["fun"]);
const submit = () => {
  emits("fun");
};

defineExpose({
  openDialog,
  closeDilog
});
</script>

页面中使用

<template>
	<el-button @click="openDialogFun">haaha</el-button>
	<FullScreenDialog ref="hdialog" @fun="dfun">
      <el-scrollbar max-height="800px">
        <h2>111111</h2>
        <h2>111111</h2>
        <!-- <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2>
        <h2>111111</h2> -->
      </el-scrollbar>
    </FullScreenDialog>
</template>
<script lant=ts>
import FullScreenDialog from "@/components/FullScreenDialog/index.vue";
const hdialog = ref();

const openDialogFun = () => {
  hdialog.value!.openDialog("修改用户");
};
const dfun = () => {
  alert("执行业务代码……");
  hdialog.value.closeDilog();
};
</script>