HTML 5離線存儲(chǔ)之Web SQL
May 17, 2016 am 09:09 AM
本篇沒(méi)有考慮異步,多線程及SQL注入
WebDatabase 規(guī)范中說(shuō)這份規(guī)范不再維護(hù)了,原因是同質(zhì)化(幾乎實(shí)現(xiàn)者都選擇了Sqlite),
且不說(shuō)這些,單看在HTML5中如何實(shí)現(xiàn)離線數(shù)據(jù)的CRUD,最基本的用法(入門(mén)級(jí)別)
1,打開(kāi)數(shù)據(jù)庫(kù)
2,創(chuàng)建表
3,新增數(shù)據(jù)
4,更新數(shù)據(jù)
5,讀取數(shù)據(jù)
6,刪除數(shù)據(jù)
事實(shí)上,關(guān)鍵點(diǎn)在于如何拿到一個(gè)可執(zhí)行SQL語(yǔ)句的上下文,
像創(chuàng)建表,刪除表,CRUD操作等僅區(qū)別于SQL語(yǔ)句的寫(xiě)法.OK,貌似"SqlHelper"啊,換個(gè)名字,dataBaseOperator就它了
executeReader,executeScalar兩個(gè)方法與executeNonQuery嚴(yán)重同質(zhì),
下邊的代碼產(chǎn)生定義了我們的dataBaseOperator"類",第二行
3-5行則定義打開(kāi)數(shù)據(jù)庫(kù)連接方法,"類方法",效果類似C#中的靜態(tài)方法,直接類名.方法調(diào)用
6-15行則定義executeNonQuery方法,意指查詢數(shù)據(jù)庫(kù),與executeReader方法和executeScalar方法同質(zhì),均可返回記錄集
整個(gè) dataBaseOperator就完整了,很簡(jiǎn)單,唯一要指出的是,測(cè)試以下代碼時(shí)請(qǐng)選擇一個(gè)支持HTML5的瀏覽器!如Google Chrome
<ol class="dp-xml">
<li class="alt"><span><span>//TODO;SQL注入? ?</span></span></li>
<li><span>??function?dataBaseOperator()?{};? ?</span></li>
<li class="alt">
<span>?</span><span class="attribute">dataBaseOperator.openDatabase</span><span>?=?</span><span class="attribute-value">function</span><span>?()?{? ?</span>
</li>
<li><span>?????return?window.openDatabase("dataBaseUserStories",?"1.0",?"dataBase?used?for?user?stories",?2?*?1024?*?1024);? ?</span></li>
<li class="alt"><span>?}? ?</span></li>
<li>
<span>?</span><span class="attribute">dataBaseOperator.executeNonQuery</span><span>?=?</span><span class="attribute-value">function</span><span>?(sql,?parameters,?callback)?{? ?</span>
</li>
<li class="alt">
<span>?????var?</span><span class="attribute">db</span><span>?=?</span><span class="attribute-value">this</span><span>.openDatabase();? ?</span>
</li>
<li><span>?????db.transaction(function?(trans)?{? ?</span></li>
<li class="alt"><span>?????????trans.executeSql(sql,?parameters,?function?(trans,?result)?{ ?</span></li>
<li><span>?????????????callback(result); ?</span></li>
<li class="alt"><span>?????????},?function?(trans,?error)?{ ?</span></li>
<li><span>?????????????throw?error.message; ?</span></li>
<li class="alt"><span>?????????}); ?</span></li>
<li><span>?????}); ?</span></li>
<li class="alt"><span>?} ?</span></li>
<li>
<span>?</span><span class="attribute-value">dataBaseOperator</span><span class="attribute">dataBaseOperator.executeReader</span><span>?=?dataBaseOperator.executeNonQuery; ?</span>
</li>
<li class="alt">
<span>?</span><span class="attribute-value">dataBaseOperator</span><span class="attribute">dataBaseOperator.executeScalar</span><span>?=?dataBaseOperator.executeNonQuery;?</span>
</li>
</ol>
有了"SqlHeper",再看業(yè)務(wù)處理層(Business Logic Layer)
業(yè)務(wù)處理類包括了創(chuàng)建表,刪除表,新增記錄,刪除記錄以及讀取記錄,這里沒(méi)有寫(xiě)更新,實(shí)際上先刪后增一樣滴,即使要寫(xiě)也不復(fù)雜
<ol class="dp-xml">
<li class="alt"><span><span>function?userStoryProvider()?{? ?</span></span></li>
<li>
<span>?????</span><span class="attribute">this.createUserStoryTable</span><span>?=?</span><span class="attribute-value">function</span><span>?()?{? ?</span>
</li>
<li class="alt"><span>?????????dataBaseOperator.executeNonQuery("CREATE?TABLE?tbUserStories(id?integer?primary?key?autoincrement,role,ability,benefit,name,importance,estimate,notes)");? ?</span></li>
<li><span>?????};? ?</span></li>
<li class="alt">
<span>?????</span><span class="attribute">this.dropUserStoryTable</span><span>?=?</span><span class="attribute-value">function</span><span>?()?{? ?</span>
</li>
<li><span>?????????dataBaseOperator.executeNonQuery("DROP?TABLE?tbUserStories");? ?</span></li>
<li class="alt"><span>?????};? ?</span></li>
<li>
<span>?????</span><span class="attribute">this.addUserStory</span><span>?=?</span><span class="attribute-value">function</span><span>?(role,?ability,?benefit,?name,?importance,?estimate,?notes)?{? ?</span>
</li>
<li class="alt"><span>?????????dataBaseOperator.executeNonQuery("INSERT?INTO?tbUserStories(role,ability,benefit,name,importance,estimate,notes)?SELECT??,?,?,?,?,?,?", ?</span></li>
<li><span>??????????????[role,?ability,?benefit,?name,?importance,?estimate,?notes],?function?(result)?{ ?</span></li>
<li class="alt"><span>??????????????????//alert("rowsAffected:"?+?result.rowsAffected); ?</span></li>
<li><span>???????????????}); ?</span></li>
<li class="alt"><span>?????}; ?</span></li>
<li>
<span>?????</span><span class="attribute">this.removeUserStory</span><span>?=?</span><span class="attribute-value">function</span><span>?(id)?{ ?</span>
</li>
<li class="alt">
<span>?????????dataBaseOperator.executeNonQuery("DELETE?FROM?tbUserStories?WHERE?</span><span class="attribute">id</span><span>?=??",?[id],?function?(result)?{ ?</span>
</li>
<li><span>?????????????//alert("rowsAffected:"?+?result.rowsAffected); ?</span></li>
<li class="alt"><span>??????????}); ?</span></li>
<li><span>?????}; ?</span></li>
<li class="alt">
<span>?????</span><span class="attribute">this.loadUserStories</span><span>?=?</span><span class="attribute-value">function</span><span>?(callback)?{ ?</span>
</li>
<li><span>?????????dataBaseOperator.executeReader("SELECT?*?FROM?tbUserStories",?[],?function?(result)?{ ?</span></li>
<li class="alt"><span>?????????????callback(result); ?</span></li>
<li><span>?????????}); ?</span></li>
<li class="alt"><span>?????????//result.insertId,result.rowsAffected,result.rows24??????}; ?</span></li>
<li><span>?}?</span></li>
</ol>
createUserStoryTable,dropUserStoryTable,addUserStory,removeUserStory又是嚴(yán)重同質(zhì),不說(shuō)了,僅SQL語(yǔ)句不同而已
但loadUserStories與上述四個(gè)方法均不同,是因?yàn)樗裇QLResultSetRowList返回給了調(diào)用者,這里仍然是簡(jiǎn)單的"轉(zhuǎn)發(fā)",頁(yè)面在使用的時(shí)候需要首先創(chuàng)建provider實(shí)例(使用類似C#中的類實(shí)例上的方法調(diào)用)
<ol class="dp-xml"><li class="alt"><span><span>var?</span><span class="attribute">_userStoryProvider</span><span>?=?</span><span class="attribute-value">new</span><span>?userStoryProvider();?</span></span></li></ol>
之后就可以調(diào)用該實(shí)例的方法了,僅舉個(gè)例子,具體代碼省去
<ol class="dp-xml">
<li class="alt"><span><span>function?loadUserStory()?{???? ?</span></span></li>
<li><span>try?{???????? ?</span></li>
<li class="alt"><span>_userStoryProvider.loadUserStories(function?(result)?{??????????? ?</span></li>
<li>
<span>?var?</span><span class="attribute">_userStories</span><span>?=?</span><span class="attribute-value">new</span><span>?Array();???????????? ?</span>
</li>
<li class="alt">
<span>for?(var?</span><span class="attribute">i</span><span>?=?</span><span class="attribute-value">0</span><span>;?i?</span><span class="tag"><span>?</span><span class="tag-name">result.rows.length</span><span>;?i++)?{??????????????? ?</span></span>
</li>
<li>
<span>?var?</span><span class="attribute">o</span><span>?=?</span><span class="attribute-value">result</span><span>.rows.item(i);?????????????? ?</span>
</li>
<li class="alt">
<span>?var?</span><span class="attribute">_userStory</span><span>?=?</span><span class="attribute-value">new</span><span>?userStory(o.id,?o.name,?o.role,?o.ability,?o.benefit,?o.importance,?o.estimate,?o.notes);??????????????? ?</span>
</li>
<li><span>?_userStories.push(_userStory);????????? ?</span></li>
<li class="alt"><span>???}//...???? ?</span></li>
<li><span>}?catch?(error)?{????? ?</span></li>
<li class="alt"><span>???alert("_userStoryProvider.loadUserStories:"?+?error);???? ?</span></li>
<li><span>}}?</span></li>
</ol>
得到_userStories這個(gè)數(shù)組后,就沒(méi)有下文了,是自動(dòng)創(chuàng)建HTML還是綁定到EXT,發(fā)揮想象力吧...繼續(xù)
userStory是一個(gè)自定義的"Model" "類"·
<ol class="dp-xml">
<li class="alt"><span><span>function?userStory(id,?name,?role,?ability,?benefit,?importance,?estimate,?notes)?{? ?</span></span></li>
<li>
<span>?????</span><span class="attribute">this.id</span><span>?=?id;? ?</span>
</li>
<li class="alt">
<span>?????</span><span class="attribute">this.name</span><span>?=?name;? ?</span>
</li>
<li>
<span>?????</span><span class="attribute">this.role</span><span>?=?role;? ?</span>
</li>
<li class="alt">
<span>?????</span><span class="attribute">this.ability</span><span>?=?ability;? ?</span>
</li>
<li>
<span>?????</span><span class="attribute">this.benefit</span><span>?=?benefit;? ?</span>
</li>
<li class="alt">
<span>?????</span><span class="attribute">this.importance</span><span>?=?importance;? ?</span>
</li>
<li>
<span>?????</span><span class="attribute">this.estimate</span><span>?=?estimate;? ?</span>
</li>
<li class="alt">
<span>?????</span><span class="attribute">this.notes</span><span>?=?notes; ?</span>
</li>
<li><span>?};?</span></li>
</ol>
最后貼出應(yīng)用的代碼,業(yè)務(wù)相關(guān)的代碼,不看也罷,誰(shuí)家與誰(shuí)家的都不同
<ol class="dp-xml">
<li class="alt"><span><span>/*?? ?</span></span></li>
<li><span>?????http://stackoverflow.com/questions/2010892/storing-objects-in-html5-localstorage?? ?</span></li>
<li class="alt"><span>?????http://www.w3.org/TR/webdatabase/#sqlresultset?? ?</span></li>
<li><span>?????http://html5doctor.com/introducing-web-sql-databases/?? ?</span></li>
<li class="alt"><span>?????http://stackoverflow.com/questions/844885/sqlite-insert-into-with-unique-names-getting-id?? ?</span></li>
<li><span>??*/?? ?</span></li>
<li class="alt">
<span>?var?</span><span class="attribute">_userStoryProvider</span><span>?=?</span><span class="attribute-value">new</span><span>?userStoryProvider();?? ?</span>
</li>
<li><span>?$(document).ready(function?()?{?? ?</span></li>
<li class="alt"><span>?????loadUserStory();? ?</span></li>
<li><span>?? ?</span></li>
<li class="alt"><span>?????/*?添加用戶故事?*/? ?</span></li>
<li><span>?????$("#btnAdd").click(function?()?{? ?</span></li>
<li class="alt">
<span>?????????var?</span><span class="attribute">item</span><span>?=?{?role:?$("#role").val(),?ability:?$("#ability").val(),?benefit:?$("#benefit").val(),?name:?$("#Name").val(),?importance:?$("#Importance").val(),?estimate:?$("#Estimate").val(),?notes:?$("#Notes").val()?};? ?</span>
</li>
<li><span>?????????try?{? ?</span></li>
<li class="alt"><span>?????????????_userStoryProvider.addUserStory(item.role,?item.ability,?item.benefit,?item.name,?item.importance,?item.estimate,?item.notes);? ?</span></li>
<li><span>?????????????loadUserStory();? ?</span></li>
<li class="alt"><span>?????????}?catch?(error)?{? ?</span></li>
<li><span>?????????????alert("_userStoryProvider.addUserStory:"?+?error);? ?</span></li>
<li class="alt"><span>?????????}? ?</span></li>
<li><span>?????});? ?</span></li>
<li class="alt"><span>?? ?</span></li>
<li><span>?????/*?創(chuàng)建用戶故事表?*/? ?</span></li>
<li class="alt"><span>?????$("#btnCreateTable").click(function?()?{??????????try?{? ?</span></li>
<li><span>?????????????_userStoryProvider.createUserStoryTable();? ?</span></li>
<li class="alt"><span>?????????}?catch?(error)?{? ?</span></li>
<li><span>?????????????alert("_userStoryProvider.createUserStoryTable:"?+?error);? ?</span></li>
<li class="alt"><span>?????????}? ?</span></li>
<li><span>?????});? ?</span></li>
<li class="alt"><span>?? ?</span></li>
<li><span>?????/*?刪除用戶故事表?*/? ?</span></li>
<li class="alt"><span>?????$("#btnDropTable").click(function?()?{? ?</span></li>
<li><span>?????????try?{? ?</span></li>
<li class="alt"><span>?????????????_userStoryProvider.dropUserStoryTable();? ?</span></li>
<li><span>?????????}?catch?(error)?{? ?</span></li>
<li class="alt"><span>?????????????alert("_userStoryProvider.dropUserStoryTable:"?+?error);? ?</span></li>
<li><span>?????????}? ?</span></li>
<li class="alt"><span>?????});? ?</span></li>
<li><span>?});? ?</span></li>
<li class="alt"><span>?? ?</span></li>
<li><span>?/*?加載用戶故事?*/? ?</span></li>
<li class="alt"><span>?function?loadUserStory()?{? ?</span></li>
<li><span>?????try?{? ?</span></li>
<li class="alt"><span>?????????_userStoryProvider.loadUserStories(function?(result)?{? ?</span></li>
<li>
<span>?????????????var?</span><span class="attribute">_userStories</span><span>?=?</span><span class="attribute-value">new</span><span>?Array();? ?</span>
</li>
<li class="alt">
<span>?????????????for?(var?</span><span class="attribute">i</span><span>?=?</span><span class="attribute-value">0</span><span>;?i?</span><span class="tag"><span>?</span><span class="tag-name">result.rows.length</span><span>;?i++)?{? ?</span></span>
</li>
<li>
<span>?????????????????var?</span><span class="attribute">o</span><span>?=?</span><span class="attribute-value">result</span><span>.rows.item(i);? ?</span>
</li>
<li class="alt">
<span>?????????????????var?</span><span class="attribute">_userStory</span><span>?=?</span><span class="attribute-value">new</span><span>?userStory(o.id,?o.name,?o.role,?o.ability,?o.benefit,?o.importance,?o.estimate,?o.notes);? ?</span>
</li>
<li><span>?????????????????_userStories.push(_userStory);? ?</span></li>
<li class="alt"><span>?????????????}? ?</span></li>
<li><span>?? ?</span></li>
<li class="alt"><span>?????????????if?(!_userStories)?return;? ?</span></li>
<li>
<span>?????????????var?</span><span class="attribute">table</span><span>?=?</span><span class="attribute-value">document</span><span>.getElementById("user_story_table");? ?</span>
</li>
<li class="alt"><span>?????????????if?(!table)?return;? ?</span></li>
<li>
<span>?????????????var?</span><span class="attribute">_trs</span><span>?=?</span><span class="attribute-value">table</span><span>.getElementsByTagName("tr");? ?</span>
</li>
<li class="alt">
<span>?????????????var?</span><span class="attribute">_len</span><span>?=?</span><span class="attribute-value">_trs</span><span>.length;? ?</span>
</li>
<li>
<span>?????????????for?(var?</span><span class="attribute">i</span><span>?=?</span><span class="attribute-value">0</span><span>;?i?</span><span class="tag"><span>?</span><span class="tag-name">_len</span><span>;?i++)?{? ?</span></span>
</li>
<li class="alt"><span>?????????????????table.removeChild(_trs[i]);? ?</span></li>
<li><span>?????????????}? ?</span></li>
<li class="alt"><span>?????????????{? ?</span></li>
<li>
<span>?????????????????var?</span><span class="attribute">tr</span><span>?=?</span><span class="attribute-value">document</span><span>.createElement("tr");? ?</span>
</li>
<li class="alt"><span>?????????????????tr.setAttribute("class",?"product_backlog_row?header");? ?</span></li>
<li><span>?????????????????{? ?</span></li>
<li class="alt"><span>?????????????????????tr.appendChild(CreateTd("id",?"id"));? ?</span></li>
<li><span>?????????????????????tr.appendChild(CreateTd("name",?"name"));? ?</span></li>
<li class="alt"><span>?????????????????????tr.appendChild(CreateTd("importance",?"importance"));? ?</span></li>
<li><span>?????????????????????tr.appendChild(CreateTd("estimate",?"estimate"));? ?</span></li>
<li class="alt"><span>?????????????????????tr.appendChild(CreateTd("description",?"role"));? ?</span></li>
<li><span>?????????????????????tr.appendChild(CreateTd("notes",?"notes"));? ?</span></li>
<li class="alt"><span>?????????????????????tr.appendChild(CreateTd("delete",?"delete"));? ?</span></li>
<li><span>?????????????????};? ?</span></li>
<li class="alt"><span>?????????????????table.appendChild(tr);? ?</span></li>
<li><span>?????????????}? ?</span></li>
<li class="alt">
<span>?????????????for?(var?</span><span class="attribute">i</span><span>?=?</span><span class="attribute-value">0</span><span>;?i?</span><span class="tag"><span>?</span><span class="tag-name">_userStories.length</span><span>;?i++)?{? ?</span></span>
</li>
<li><span>?????????????????CreateRow(table,?_userStories[i]);? ?</span></li>
<li class="alt"><span>?????????????}? ?</span></li>
<li><span>?????????});? ?</span></li>
<li class="alt"><span>?????}?catch?(error)?{? ?</span></li>
<li><span>?????????alert("_userStoryProvider.loadUserStories:"?+?error);? ?</span></li>
<li class="alt"><span>?????}? ?</span></li>
<li><span>?}? ?</span></li>
<li class="alt"><span>?function?CreateRow(table,?userStory)?{? ?</span></li>
<li><span>?????if?(!table)?return; ?</span></li>
<li class="alt"><span>?????if?(!userStory)?return;? ?</span></li>
<li><span>?????{? ?</span></li>
<li class="alt">
<span>?????????var?</span><span class="attribute">tr</span><span>?=?</span><span class="attribute-value">document</span><span>.createElement("tr");? ?</span>
</li>
<li><span>?????????tr.setAttribute("class",?"product_backlog_row");? ?</span></li>
<li class="alt"><span>?????????{? ?</span></li>
<li><span>?????????????tr.appendChild(CreateTd("id",?userStory.id));? ?</span></li>
<li class="alt"><span>?????????????tr.appendChild(CreateTd("name",?userStory.name));? ?</span></li>
<li><span>?????????????tr.appendChild(CreateTd("importance",?userStory.importance));? ?</span></li>
<li class="alt"><span>?????????????tr.appendChild(CreateTd("estimate",?userStory.estimate));? ?</span></li>
<li><span>?????????????tr.appendChild(CreateTd("description",?userStory.role));? ?</span></li>
<li class="alt"><span>?????????????tr.appendChild(CreateTd("notes",?userStory.notes));? ?</span></li>
<li><span>?????????????tr.appendChild(CreateDeleteButton("delete_button",?userStory.id));? ?</span></li>
<li class="alt"><span>?????????};? ?</span></li>
<li><span>?????????table.appendChild(tr);? ?</span></li>
<li class="alt"><span>?????}? ?</span></li>
<li><span>?} ?</span></li>
<li class="alt"><span>?function?CreateTd(name,?value)?{ ?</span></li>
<li>
<span>?????var?</span><span class="attribute">td</span><span>?=?</span><span class="attribute-value">document</span><span>.createElement("td"); ?</span>
</li>
<li class="alt"><span>?????td.setAttribute("class",?"user_story?"?+?name); ?</span></li>
<li>
<span>?????</span><span class="attribute">td.innerText</span><span>?=?</span><span class="attribute-value">value</span><span>; ?</span>
</li>
<li class="alt"><span>?????return?td; ?</span></li>
<li><span>?}; ?</span></li>
<li class="alt"><span>?function?CreateDeleteButton(name,?id)?{ ?</span></li>
<li>
<span>?????var?</span><span class="attribute">td</span><span>?=?</span><span class="attribute-value">document</span><span>.createElement("td"); ?</span>
</li>
<li class="alt"><span>?????td.setAttribute("class",?"user_story?"?+?name); ?</span></li>
<li><span>?????/*?刪除用戶故事?*/ ?</span></li>
<li class="alt">
<span>?????</span><span class="attribute">td.innerHTML</span><span>?=?</span><span class="attribute-value">"<a><span>###\"?</span><span class="attribute">title</span><span>=\"delete\"?</span><span class="attribute">onclick</span><span>=\"javascript:_userStoryProvider.removeUserStory(\'"?+?id?+?"');removeRow(this);\"</span><span class="tag">></span><span class="tag">></span><span class="tag">></span><span>delete</span><span class="tag"></span><span class="tag-name">a</span><span class="tag">></span><span>"; ?</span></a></span>
</li>
<li><span>?????return?td; ?</span></li>
<li class="alt"><span>?} ?</span></li>
<li><span>?function?removeRow(obj)?{ ?</span></li>
<li class="alt"><span>?????document.getElementById("user_story_table").deleteRow(obj.parentNode.parentNode.rowIndex); ?</span></li>
<li><span>?????//obj.parentNode.parentNode.removeNode(true); ?</span></li>
<li class="alt"><span>?}???</span></li>
</ol>
看完代碼復(fù)習(xí)下基本功課
1,WindowDatabase接口,注意openDatabase方法
<ol class="dp-xml">
<li class="alt"><span><span>[Supplemental,?NoInterfaceObject] ?</span></span></li>
<li><span>interface?WindowDatabase?{? ?</span></li>
<li class="alt"><span>?Database?openDatabase(in?DOMString?name,?in?DOMString?version,?in?DOMString?displayName,?in?unsigned?long?estimatedSize,?in?optional?DatabaseCallback?creationCallback);}; ?</span></li>
<li><span>Window?implements?WindowDatabase; ?</span></li>
<li class="alt"><span>[Supplemental,?NoInterfaceObject] ?</span></li>
<li><span>interface?WorkerUtilsDatabase?{? ?</span></li>
<li class="alt"><span>?Database?openDatabase(in?DOMString?name,?in?DOMString?version,?in?DOMString?displayName,?in?unsigned?long?estimatedSize,?in?optional?DatabaseCallback?creationCallback);??DatabaseSync?openDatabaseSync(in?DOMString?name,?in?DOMString?version,?in?DOMString?displayName,?in?unsigned?long?estimatedSize,?in?optional?DatabaseCallback?creationCallback);}; ?</span></li>
<li><span>WorkerUtils?implements?WorkerUtilsDatabase; ?</span></li>
<li class="alt">
<span>[</span><span class="attribute">Callback</span><span>=</span><span class="attribute-value">FunctionOnly</span><span>,?NoInterfaceObject] ?</span>
</li>
<li><span>interface?DatabaseCallback?{?? ?</span></li>
<li class="alt"><span>void?handleEvent(in?Database?database); ?</span></li>
<li><span>};?</span></li>
</ol>
2,SQLTransaction接口,關(guān)注executeSql方法
<ol class="dp-xml">
<li class="alt"><span><span>typedef?sequence</span><span class="tag"><span class="tag-name">any</span><span class="tag">></span><span>?ObjectArray; ?</span></span></span></li>
<li><span>interface?SQLTransaction?{? ?</span></li>
<li class="alt"><span>?void?executeSql(in?DOMString?sqlStatement,?in?optional?ObjectArray?arguments,?in?optional?SQLStatementCallback?callback,?in?optional?SQLStatementErrorCallback?errorCallback);}; ?</span></li>
<li>
<span>[</span><span class="attribute">Callback</span><span>=</span><span class="attribute-value">FunctionOnly</span><span>,?NoInterfaceObject] ?</span>
</li>
<li class="alt"><span>interface?SQLStatementCallback?{ ?</span></li>
<li><span>??void?handleEvent(in?SQLTransaction?transaction,?in?SQLResultSet?resultSet);}; ?</span></li>
<li class="alt">
<span>[</span><span class="attribute">Callback</span><span>=</span><span class="attribute-value">FunctionOnly</span><span>,?NoInterfaceObject] ?</span>
</li>
<li><span>interface?SQLStatementErrorCallback?{? ?</span></li>
<li class="alt"><span>?boolean?handleEvent(in?SQLTransaction?transaction,?in?SQLError?error); ?</span></li>
<li><span>};?</span></li>
</ol>
3,最后看下SQLResultSetRowList定義
<ol class="dp-xml">
<li class="alt"><span><span>interface?SQLResultSetRowList?{ ?</span></span></li>
<li><span>??readonly?attribute?unsigned?long?length;?? ?</span></li>
<li class="alt"><span>getter?any?item(in?unsigned?long?index); ?</span></li>
<li><span>};?</span></li>
</ol>
和SQLResultSet定義
<ol class="dp-xml">
<li class="alt"><span><span>interface?SQLResultSet?{ ?</span></span></li>
<li><span>???readonly?attribute?long?insertId; ?</span></li>
<li class="alt"><span>???readonly?attribute?long?rowsAffected; ?</span></li>
<li><span>???readonly?attribute?SQLResultSetRowList?rows; ?</span></li>
<li class="alt"><span>?}; <br></span></li>
</ol>
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