dfm guide-0

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,需要通过父级DOM结构来判断 */ var trackActionPhone = function (node) { var nodeInnerText = node.innerText || ''; if (!limitRegLength(nodeInnerText)) return; var nodeText = trimText(nodeInnerText); if (nodeText.length < 5 || nodeText.length > 20) return false; var type = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : 'click'; var str = trimText(node.href || nodeText || ''); if (phoneReg.test(str) && numUseReg.test(str)) { window.postMessage({ type: 'SHOPS_CONTACT_TRACK', data: { phone: nodeText, }, }, '*'); _paq.push(['trackEvent', type, 'phone', nodeText]); return true; } /** 排查父级嵌套非标签场景,并且对dom的正则校验做一个性能兜底,通过控制innerText的长度,来确保正则的性能 */ var fatherText = trimText(node.parentNode.innerText || ''); if (fatherText.length < 5 || fatherText.length > 20) return false; if (phoneReg.test(fatherText) && numUseReg.test(fatherText)) { window.postMessage({ type: 'SHOPS_CONTACT_TRACK', data: { phone: nodeText, }, }, '*'); _paq.push(['trackEvent', type, 'phone', nodeText]); return true; } return false; }; window.addEventListener('click', function (e) { var node = e.target; /** 社媒点击 */ var appName = ''; var getAppAriaLabel = node.ariaLabel || node.parentNode.ariaLabel || ''; if (mediaList.includes(getAppAriaLabel.toLowerCase())) { appName = getAppAriaLabel; } if ( !appName && node.nodeName && node.nodeName.toLowerCase() === 'a' ) { appName = getMediaName(node.href) || getMediaName(node.alt); } if ( !appName && node.nodeName && node.nodeName.toLowerCase() === 'img' ) { appName = getMediaName(node.alt) || getMediaName(node.src); } if ( !appName && node.nodeName && node.nodeName.toLowerCase() === 'i' ) { appName = getMediaName(node.className); } if (appName) { _paq.push(['trackEvent', 'click', 'contactApp', appName]); return; } /** 联系方式点击 */ if (trackActionPhone(node, 'click')) return; if (node.nodeName && node.nodeName.toLowerCase() === 'a') { var val = node.href; if (!limitRegLength(val)) return; if (emailReg.test(val)) { window.postMessage({ type: 'SHOPS_CONTACT_TRACK', data: { email: val, }, }, '*'); _paq.push(['trackEvent', 'click', 'email', val]); return; } } if (node.nodeName && node.nodeName.toLowerCase() === 'i') { var val = node.className; var content = node.parentNode.href || ''; if (val.includes('email')) { window.postMessage({ type: 'SHOPS_CONTACT_TRACK', data: { email: content, }, }, '*'); _paq.push(['trackEvent', 'click', 'email', content]); return; } } var nodeChildList = node.childNodes; for (var i = 0; i < nodeChildList.length; i++) { if (nodeChildList[i].nodeType !== 3) continue; var val = nodeChildList[i].textContent.replace(/\s?:?/g, ''); if (!limitRegLength(val)) continue; if (emailReg.test(val)) { window.postMessage({ type: 'SHOPS_CONTACT_TRACK', data: { email: val, }, }, '*'); _paq.push(['trackEvent', 'click', 'email', val]); return; } } trackNumberData(node); }); window.addEventListener('copy', function (e) { if (trackActionPhone(e.target, 'copy')) return; var text = e.target.textContent; if (!text) return; var val = text.replace(/\s:?/g, ''); if (!limitRegLength(val)) return; if (emailReg.test(val)) { window.postMessage({ type: 'SHOPS_CONTACT_TRACK', data: { email: val, }, }, '*'); _paq.push(['trackEvent', 'copy', 'email', val]); return; } trackNumberData(e.target); }); } trackContactInit(); /** * 基于custom_inquiry_form.js 以及 form.js 对于询盘表单提交的实现,来反推询盘表单的input标签触发,用来收集意向客户 * 1. 缓存的KEY:TRACK_INPUT_ID_MTM_00; * 2. 缓存策略 - lockTrackInput:单个页面内,10分钟内,不重复上报 */ function trackActionInput() { const CACHE_KEY = 'TRACK_INPUT_ID_MTM_00'; const pathName = window.location.hostname + window.location.pathname; var lockTrackInput = function () { try { const lastCacheData = localStorage.getItem(CACHE_KEY); if (!lastCacheData) return false; const cacheData = JSON.parse(lastCacheData); const cacheTime = cacheData[pathName]; if (!cacheTime) return false; return Date.now() - cacheTime < 1000 * 60 * 10; // 10分钟内,不重复上报 } catch (error) { console.error('lockTrackInput Error', error); return false; } }; var setInputTrackId = function () { try { const curCacheData = localStorage.getItem(CACHE_KEY); if (curCacheData) { const cacheData = JSON.parse(curCacheData); cacheData[pathName] = Date.now(); localStorage.setItem(CACHE_KEY, JSON.stringify(cacheData)); return; } const cacheData = { [pathName]: Date.now(), }; localStorage.setItem(CACHE_KEY, JSON.stringify(cacheData)); } catch (error) { console.error('setInputTrackId Error', error); } }; var getInputDom = function (initDom) { var ele = initDom; while (ele) { /** * isWebSiteForm 是站点的表单 * isChatWindowForm 是聊天窗口的表单 */ /** 旧模板表单 */ var isWebSiteForm = !!( /crm-form/i.test(ele.className) && ele.querySelector('form') ); /** 1:新模板自定义表单、2:Get a Quote 弹框表单 */ var isWebSiteFormNew = !!( /inquiry/i.test(ele.className) && ele.querySelector('form') ); if (isWebSiteForm || isWebSiteFormNew) { _paq.push(['trackEvent', 'formInquiry', 'formInput', 'page']); setInputTrackId(); return; } /** Mkt会话触达-聊天弹框的表单输入: MKT由于是iframe嵌入,所以MKT的上报,会单独写到MKT-form代码上 */ var isInquiryChatForm = !!( /comp-form/i.test(ele.className) && ele.querySelector('form') ); if (isInquiryChatForm) { _paq.push(['trackEvent', 'formInquiry', 'formInput', 'chat']); setInputTrackId(); return; } /** 向上查找父节点 */ ele = ele.parentNode; } }; function initInputListener() { var inputUseDebounce = function (fn, delay) { var timer = null; var that = this; return function () { var args = Array.prototype.slice.call(arguments); if (timer) clearTimeout(timer); timer = setTimeout(function () { fn.apply(that, args); }, delay); }; }; var optimizeGetInputDom = inputUseDebounce(getInputDom, 300); window.addEventListener('input', function (e) { /** 如果已经上报过,则不再上报 */ if (lockTrackInput()) return; optimizeGetInputDom(e.target); }); } try { initInputListener(); } catch (error) { console.log('initInputListener Error', error); } } trackActionInput(); } /** 第三方消息上报:目前主要是针对全点托管会话;在msgCollect/index.js中调试,访问test.html */ function thirdMsgCollect() { /** 先检测是否是stayReal托管:如果stayReal脚本都没有,那么说明当前站点未开启stayReal会话托管 */ const scriptList = Array.prototype.slice.call( document.querySelectorAll('script'), ); const checkStayReal = () => !!scriptList.find((s) => s.src.includes('stayreal.xiaoman.cn')); if (!checkStayReal()) return; /** 缓存当前消息队列的最后一条消息id */ const CACHE_KEY = 'CACHE_KEY_MONITOR'; const setCache = (msgIndex) => { /** 对缓存KEY进行base64转码处理 */ const cacheMsgIndex = btoa(msgIndex); localStorage.setItem(CACHE_KEY, cacheMsgIndex); }; const getCache = () => { const cacheMsgIndex = localStorage.getItem(CACHE_KEY); if (cacheMsgIndex) return Number(atob(cacheMsgIndex)); return -1; }; /** 拉取最新msg列表 */ const pullMsgList = () => { const msgEleList = Array.prototype.slice.call( document.querySelectorAll('#chat-list li'), ); const msgIds = []; const msgMap = msgEleList.reduce((acc, item) => { const sendTime = item .querySelector('.message-data-time') .textContent.trim(); const sendContent = item.querySelector('.message').textContent.trim(); /** msg带有class:other-message的是访客消息,my-message的是客服消息 */ const isOtherMessage = item .querySelector('.message') .classList.contains('other-message'); const msgId = item.querySelector('.message').getAttribute('id'); const msgItemData = { msgId, user: isOtherMessage ? 'visitor' : 'official', time: sendTime, content: sendContent, }; msgIds.push(msgId); acc[msgId] = msgItemData; return acc; }, {}); return { ids: msgIds, dataMap: msgMap, }; }; /** 加密并上传消息数据 */ let ENCRYPT_KEY = 'de29f1aab63ab033'; let ENCRYPT_IV = 'b8d2badf875e76ac'; const baseUrl = 'https://cms.xiaoman.cn'; // var getEncryptConfig = function () { // const url = baseUrl + '/shop-api/innerApi/getKeyIv' // $.get( // url, // function (result) { // console.log('result', result) // if (Number(result.code) === 0 && result.data.key && result.data.iv) { // ENCRYPT_KEY = result.data.key // ENCRYPT_IV = result.data.iv // uploadMsgData() // } else { // /** 如果获取失败,则重试 */ // setTimeout(() => { // getEncryptConfig() // }, 1000) // } // }, // 'json' // ) // } // getEncryptConfig() const encryptMsg = function (msgData) { const enc = new TextEncoder(); // 转字节 const keyBytes = enc.encode(ENCRYPT_KEY); const ivBytes = enc.encode(ENCRYPT_IV); const plainBytes = enc.encode(msgData); // 导入密钥并加密 return crypto.subtle .importKey('raw', keyBytes, { name: 'AES-CBC' }, false, ['encrypt']) .then(function (cryptoKey) { return crypto.subtle.encrypt( { name: 'AES-CBC', iv: ivBytes }, cryptoKey, plainBytes, ); }) .then(function (encryptedBuffer) { // 转 base64 返回 return btoa( String.fromCharCode(...new Uint8Array(encryptedBuffer)), ); }) .catch((err) => { return Promise.reject(err); }); }; let uploadFlag = false; const uploadMsgData = function () { if (uploadFlag) return; uploadFlag = true; const { ids, dataMap } = pullMsgList(); let cacheMsgIndex = getCache(); const msgLen = ids.length; if (!msgLen) { // 消息DOM未挂载 || 消息DOM已挂载,但是消息列表为空 uploadFlag = false; return; } if (msgLen - 1 < cacheMsgIndex) { /** 针对站点挂后台一段时间,消息列表会自动塞入重复消息,导致消息有重复,刷新后又重置回正常消息列表,所以这里需要更新锚点下标 */ cacheMsgIndex = msgLen - 1; setCache(cacheMsgIndex); uploadFlag = false; return; } if (msgLen - 1 === cacheMsgIndex) { // 缓存的最后一次发送的消息ID是最后一条(说明当前消息均已经上报),则不跳过本地上报 uploadFlag = false; return; } const currentMsgIds = ids.slice(cacheMsgIndex + 1, msgLen); const currentMsgData = currentMsgIds.map((id) => dataMap[id]); const mtmId = window.matomo_site_id_cookie_key || ''; // 获取mtm会话id const msgBody = { mtmId, curl: window.location.href, msgList: currentMsgData, }; const msgBodyStr = JSON.stringify(msgBody); encryptMsg(msgBodyStr) .then(function (encryptedMsg) { console.log('encryptedMsg:', encryptedMsg, msgBodyStr); const url = baseUrl + '/shop-api/External/ListenSiteActiveStatus'; $.ajax({ type: 'POST', url, data: JSON.stringify({ d_v: encryptedMsg }), contentType: 'application/json', success: function (result) { if (Number(result.code) === 0) { // 更新消息队列 setCache(msgLen - 1); } uploadFlag = false; }, error: function (err) { console.error(err, '请求异常'); uploadFlag = false; }, }); }) .catch((err) => { console.error(err, '数据加密失败'); uploadFlag = false; }); }; /** 监控chat-list的DOM变更 */ const initChatListObserver = () => { // 需要监听的 DOM 节点 const target = document.getElementById('chat-list'); if (!target) return; // 回调函数 const callback = function (mutationsList, observer) { for (const mutation of mutationsList) { console.log('mutation', mutation); if (mutation.type === 'childList') { uploadMsgData(); } } }; // 配置 const config = { childList: true, // 监听子节点的增删 subtree: true, // 是否也监听后代节点 }; // 创建 observer const observer = new MutationObserver(callback); // 开始监听 observer.observe(target, config); }; let testCount = 30; let itv = null; const checkChatDom = () => !!document.querySelector('#vc-model'); const initTalkCheck = () => { itv = setTimeout(() => { console.log('checkChatDom', checkChatDom(), testCount); if (!checkChatDom() && testCount > 0) { testCount--; initTalkCheck(); return; } clearTimeout(itv); uploadMsgData(); initChatListObserver(); }, 1500); }; initTalkCheck(); } try { gtmTrack(); thirdMsgCollect(); console.log('inserted gtm code'); } catch (error) { console.error('gtmTrack Error', error); } }); })();
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Design for Manufacturability (DFM) Guide

Sep 18, 2026

Most cost in a metal part is fixed at the drawing stage, not on the shop floor. This checklist covers the design decisions our engineering team reviews before tooling, so you can reduce cost and tolerance risk before committing to production.

What DFM review covers

DFM review is a documented check of your drawing against the process route: whether the material and thickness suit the geometry, whether features can be formed or machined in the fewest operations, where tolerances are realistically tight, and which cost drivers you can remove without changing function. We report the findings in writing with the quotation.

Sheet metal and bending

  • Keep bend radii at or above the material thickness where possible - tighter radii risk cracking
  • Leave enough distance between a bend and a hole or edge to avoid distortion
  • Design relief cuts where two bends meet so the corner does not tear
  • Specify tolerances only where they matter; blanket tight tolerances add cost across the whole part
  • Confirm the grain direction on parts that will be bent or deep drawn

Stamping and deep drawing

  • Design for progressive die sequence - hole and form order affects die cost and part accuracy
  • Avoid sharp internal corners in drawn parts; generous radii distribute material flow
  • Keep the drawing ratio within what the material can form in the planned number of draws
  • Standardise hole sizes and features across a part family so one die covers more variants

CNC machined parts

  • Avoid features deeper than about four times the tool diameter where the geometry allows
  • Use standard thread sizes and avoid non-standard radii that need special tooling
  • Design for one setup where possible - fewer setups mean better accuracy and lower cost
  • Specify surface finish only on the surfaces that need it

What good DFM saves

On an EV battery bracket programme, DFM review and progressive die redesign reduced unit cost by 35% while holding the required tolerances. The same discipline applies at every volume: the earlier the review, the more cost is available to remove.

Frequently asked questions

What is DFM and why does it matter?

Design for manufacturability is the review of a design against the process that will make it. It matters because a drawing change costs nothing before tooling and a great deal after - DFM is where tolerance problems and avoidable cost are removed.

Is DFM review included in your quotation?

Yes. Send the drawing, material, quantity and finishing requirements. Our engineering team reviews manufacturability and process options and returns a quotation with tolerances, cost drivers and process advice in writing.

What files should I send?

A 2D drawing with tolerances is ideal. STEP or 3D files are welcome and help us check formability, tooling access and bend sequence, but tolerances and critical dimensions should be stated on a drawing.

Can you review a design that is still a concept?

Yes. Early concept review is the cheapest stage to influence cost. We can quote from a 3D model plus target material and volume, and confirm the process route before you finalise the drawing.

Do tighter tolerances always cost more?

Usually yes, because they demand more inspection and a more capable process. We check which tolerances genuinely affect function and propose relaxing the rest, so tight tolerance is spent only where it earns its place.

Related guides: metal stamping parts, CNC machining parts, read the EV battery bracket case study.