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TEST_U='https://2r4s9p1yi1fa2jd7j43zph8r-wpengine.netdna-ssl.com/wp-content/themes/Hax/img/dino.svg' TEST_DB= { db_name:"test", table_name:"test", dbVersion:1, } say=(x='')=>(y="")=>console.log(x,y); show_img=(imgFile)=>{ var imgURL = URL.createObjectURL(imgFile); dom=document.getElementById("elephant") dom.setAttribute("src", imgURL); URL.revokeObjectURL(imgURL); } find_img=({db,table_name})=>{ var transaction = db.transaction([table_name], IDBTransaction.READ_WRITE); transaction.objectStore(table_name).get("image").onsuccess = function (event) { var imgFile = event.target.result; console.log("Got elephant!" + imgFile); } } // insert save_img = function ({db,table_name},blob) { console.log("saving",blob); var transaction = db.transaction([table_name], 'readwrite'); // IDBTransaction.READ_WRITE var put = transaction.objectStore(table_name).put(blob, "image"); } // get get_img=(u)=>fetch(u).then(x=>x.blob()) save_img1=async(a,u)=>save_img(a,await get_img(u)) insert=({db,table_name},d={})=>{ var request = db.transaction([table_name], 'readwrite') .objectStore(table_name) .add(d); request.onsuccess = say('insert success') request.onerror = say('insert fail') } find_by_index=({db,table_name},query={"name":"ccc"})=>{ var transaction = db.transaction([table_name], 'readonly'); var store = transaction.objectStore(table_name); let [k,v]=Object.entries(query) var index = store.index(k) var request = index.get(v) request.onsuccess = function (e) { var result = e.target.result; console.log(result) } } find= ({db,table_name},id=1)=> { var transaction = db.transaction(table_name); var objectStore = transaction.objectStore(table_name); var request = objectStore.get(id); request.onerror = say('err'); request.onsuccess = function( event) { let r=request.result ||{} console.log(r) }; } find_all=({db,table_name})=> { var objectStore = db.transaction(table_name).objectStore(table_name); objectStore.openCursor().onsuccess = function (event) { var cursor = event.target.result; let r=[] if (cursor) { console.log(cursor) r.push(cursor) cursor.continue(); } else { console.log('没有更多数据了！'); } console.log(r) } } remove=({db,table_name},id)=> { var request = db.transaction([table_name], 'readwrite') .objectStore(table_name) .delete(id); request.onsuccess = say('removed') } update= ({db,table_name},d={ id: 1, name: '李四', age: 35, email: 'lisi@example.com' })=> { var request = db.transaction([table_name], 'readwrite') .objectStore(table_name) .put(d); request.onsuccess = say('updated') request.onerror = say('update failed') } // (TEST_U) run=(fn=save_img1,...arg)=>{ config=TEST_DB let { db_name,table_name,dbVersion,cb }=config var request = indexedDB.open(db_name, dbVersion); request.onsuccess = function (event) { db = request.result; db.onerror = say('fail open') fn({...config,db},...arg) } request.onupgradeneeded = function (event) { db=event.target.result if ( !db.objectStoreNames.contains(table_name) ){ let o={ keyPath: 'id', autoIncrement: true , } var objectStore = db.createObjectStore(table_name,o) objectStore.createIndex('name', 'name', { unique: false }); } } request.onerror =say('error') } run(insert,{x:1,y:2,z:3})