diff --git a/web/src/designer/templates.test.ts b/web/src/designer/templates.test.ts
index 2a41651..75515a3 100644
--- a/web/src/designer/templates.test.ts
+++ b/web/src/designer/templates.test.ts
@@ -3,7 +3,7 @@ import { expect, test } from 'bun:test'
 import { generateDesigner, parseDesigner } from './document'
 import { addControl } from './edit'
 import { controlDef } from './catalog'
-import { assignmentTemplate, formNameTaken, newFormFiles, nextFormName, projectNamespace, startupForm } from './templates'
+import { assignmentTemplate, classPathError, formNameTaken, newClassFile, newFormFiles, nextFormName, projectNamespace, startupForm } from './templates'
 
 const files = [
   { path: 'Program.cs', content: 'namespace 登录\n{\n    static class Program\n    {\n        static void Main()\n        {\n            Application.Run(new Login());\n        }\n    }\n}\n' },
@@ -66,3 +66,17 @@ test('作业起点"空白工程"：Program.cs 启动空的 Form1', async () => {
   expect(program).toContain('Application.Run(new Form1())')
   expect(files.find((f) => f.path === 'Form1.Designer.cs')!.content).not.toContain('com_port')
 })
+
+test('新建类：可以带文件夹，文件夹也是命名空间的一段；名字不能重复', () => {
+  const files = [{ path: 'Program.cs', content: 'namespace 智慧校园\n{\n    static class Program { }\n}\n' }, { path: 'AppSet.cs', content: 'class AppSet { }' }]
+  expect(newClassFile('智慧校园', 'SQLHelpers/SQLHelper')).toEqual({
+    path: 'SQLHelpers/SQLHelper.cs',
+    content: 'using System;\nusing System.Collections.Generic;\nusing System.Linq;\nusing System.Text;\nusing System.Threading.Tasks;\n\nnamespace 智慧校园.SQLHelpers\n{\n    class SQLHelper\n    {\n    }\n}\n',
+  })
+  expect(newClassFile('智慧校园', 'RecordClass.cs').path).toBe('RecordClass.cs')
+  expect(classPathError(files, 'SQLHelpers/SQLBLL')).toBeNull()
+  expect(classPathError(files, 'AppSet')).toBe('已经有 AppSet.cs 了')
+  expect(classPathError(files, 'Other/AppSet')).toBe('已经有名为“AppSet”的类或窗体')
+  expect(classPathError(files, '1abc')).toContain('不能以数字开头')
+  expect(classPathError(files, 'Properties/X')).toContain('平台管理')
+})
diff --git a/web/src/designer/templates.ts b/web/src/designer/templates.ts
index 1422732..378c27f 100644
--- a/web/src/designer/templates.ts
+++ b/web/src/designer/templates.ts
@@ -22,6 +22,42 @@ export function formNameTaken(files: SourceFile[], name: string): boolean {
   return files.some((f) => f.path === `${name}.cs` || f.path === `${name}.Designer.cs` || new RegExp(`(?<![\\p{L}\\p{N}_])class\\s+${name}(?![\\p{L}\\p{N}_])`, 'u').test(f.content))
 }
 
+/**
+ * 新建类时输入的名字有什么问题（没有问题返回 null）。可以带文件夹，如 SQLHelpers/SQLHelper：
+ * 和 VS 一样，文件放进文件夹，文件夹也是命名空间的一段。
+ */
+export function classPathError(files: SourceFile[], input: string): string | null {
+  const path = input.trim().replace(/\\/g, '/').replace(/\.cs$/i, '')
+  if (!path) return '请输入类名'
+  const parts = path.split('/')
+  if (parts.some((p) => !/^[\p{L}_][\p{L}\p{N}_]*$/u.test(p))) return '类名和文件夹名只能用字母、汉字、数字、下划线，且不能以数字开头'
+  if (parts[0] === 'Properties') return 'Properties 文件夹由平台管理，请换一个文件夹'
+  if (files.some((f) => f.path.toLowerCase() === `${path}.cs`.toLowerCase())) return `已经有 ${path}.cs 了`
+  if (formNameTaken(files, parts.at(-1)!)) return `已经有名为“${parts.at(-1)}”的类或窗体`
+  return null
+}
+
+/** 新建类（VS 的"添加 → 类"）：和 VS 2012 的模板一样 */
+export function newClassFile(namespace: string, input: string): SourceFile {
+  const path = input.trim().replace(/\\/g, '/').replace(/\.cs$/i, '')
+  const parts = path.split('/')
+  const name = parts.pop()!
+  const content = `using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ${[namespace, ...parts].join('.')}
+{
+    class ${name}
+    {
+    }
+}
+`
+  return { path: `${path}.cs`, content }
+}
+
 /** Program.cs 里 Application.Run(new X()) 启动的窗体类名 */
 export function startupForm(files: SourceFile[]): string | undefined {
   const program = files.find((f) => f.path === 'Program.cs')
diff --git a/web/src/pages/WorkbenchPage.vue b/web/src/pages/WorkbenchPage.vue
index 112a0e2..de16083 100644
--- a/web/src/pages/WorkbenchPage.vue
+++ b/web/src/pages/WorkbenchPage.vue
@@ -10,7 +10,7 @@ import FormDesigner from '../designer/FormDesigner.vue'
 import { createDesignerHistory } from '../designer/history'
 import { gallery, loadGallery, projectResources, resourcePrefix, resourcesFile, RESOURCES_FILE } from '../designer/resources'
 import ResourcesDialog from '../designer/ResourcesDialog.vue'
-import { formNameTaken, isFormDesigner, newFormFiles, nextFormName, projectNamespace, startupForm } from '../designer/templates'
+import { classPathError, formNameTaken, isFormDesigner, newClassFile, newFormFiles, nextFormName, projectNamespace, startupForm } from '../designer/templates'
 import CodeEditor from '../editor/CodeEditor.vue'
 import { api } from '../api'
 import { currentUser, logout } from '../auth'
@@ -293,6 +293,41 @@ function saveResources(names: string[]) {
   filesChanged()
 }
 
+// ---------- 新建、删除类 ----------
+const newClassOpen = ref(false)
+const newClassName = ref('')
+const newClassError = computed(() => classPathError(files.value, newClassName.value))
+
+function openNewClass(show: boolean) {
+  newClassOpen.value = show
+  if (show) newClassName.value = ''
+}
+
+/** 新建类：和 VS 的"添加 → 类"一样，可以带文件夹（SQLHelpers/SQLHelper） */
+function createClass() {
+  if (newClassError.value) return
+  const created = newClassFile(projectNamespace(files.value), newClassName.value)
+  files.value.push(created)
+  filesChanged()
+  newClassOpen.value = false
+  activeTab.value = created.path
+}
+
+/** 当前标签页的普通类文件能否删除：窗体文件、Program.cs、平台生成的资源类不在这里删 */
+const deletableClass = computed(() => {
+  const path = activeTab.value
+  if (!path || activeForm.value || path === 'Program.cs' || path.startsWith('Properties/') || !path.endsWith('.cs')) return undefined
+  return forms.value.some((f) => f.code === path || f.designer === path) ? undefined : path
+})
+
+function deleteClass() {
+  const path = deletableClass.value
+  if (!path) return
+  files.value = files.value.filter((f) => f.path !== path)
+  filesChanged()
+  activeTab.value = forms.value[0]?.tab ?? files.value[0]?.path
+}
+
 // ---------- 新建、删除窗体 ----------
 const newFormOpen = ref(false)
 const newFormName = ref('')
@@ -467,6 +502,23 @@ function run() {
               <NButton size="small" type="primary" :disabled="!!newFormError" @click="createForm">创建</NButton>
             </div>
           </NPopover>
+          <NPopover trigger="click" placement="bottom-end" :show="newClassOpen" @update:show="openNewClass">
+            <template #trigger>
+              <NButton size="small" quaternary>＋ 新建类</NButton>
+            </template>
+            <div class="new-form">
+              <div>类名（也是文件名；放进文件夹时写成 SQLHelpers/SQLHelper）</div>
+              <NInput v-model:value="newClassName" size="small" placeholder="例如：AppSet" @keydown.enter="createClass" />
+              <div v-if="newClassError && newClassName.trim()" class="new-form-error">{{ newClassError }}</div>
+              <NButton size="small" type="primary" :disabled="!!newClassError" @click="createClass">创建</NButton>
+            </div>
+          </NPopover>
+          <NPopconfirm v-if="deletableClass" positive-text="删除" negative-text="取消" @positive-click="deleteClass">
+            <template #trigger>
+              <NButton size="small" quaternary>删除类</NButton>
+            </template>
+            将删除 {{ deletableClass }}，代码里用到它的地方需要自己修改。确定删除吗？
+          </NPopconfirm>
           <NButton size="small" quaternary title="相当于 VS 的“项目属性 → 资源”：添加图片和声音，代码里用 Properties.Resources.名字" @click="resourcesOpen = true">
             项目资源{{ resourceNames.length ? `（${resourceNames.length}）` : '' }}
           </NButton>