javascript代碼在ie8里報錯 document.getElementById(...) 為空或不是對象的解決方法原創

2019-11-21 00:57:25

字體：大中小

來源：轉載

供稿：網友

ie8中對于聲明文檔類型更加嚴格如下面的代碼。

運行環境： <input type='text' name='os' value='Windows平臺' style='width:100px' /> <script type="text/javascript">                 function osdo(str){                 document.getElementById("os").value=str;                 }                 </script> <input name="ostmp" type="radio" value="" onclick="osdo('')" />清空 <input name="ostmp" type="radio" value="Windows平臺" onclick="osdo('Windows平臺')" /> Windows平臺 <input name="ostmp" type="radio" value="" onclick="osdo('S60v2')" />S60v2 <input name="ostmp" type="radio" value="" onclick="osdo('S60v3')" />S60v3 <input name="ostmp" type="radio" value="" onclick="osdo('CHM')" />CHM <input name="ostmp" type="radio" value="" onclick="osdo('PDF')" />PDF <input name="ostmp" type="radio" value="" onclick="osdo('PPT')" />PPT <input name="ostmp" type="radio" value="" onclick="osdo('DOC')" />WORD <input name="ostmp" type="radio" value="" onclick="osdo('EXCEL')" />EXCEL <input name="ostmp" type="radio" value="" onclick="osdo('asp')" />asp <input name="ostmp" type="radio" value="" onclick="osdo('asp+access')" />asp+access <input name="ostmp" type="radio" value="" onclick="osdo('asp+sqlserver')" />asp+sqlserver <input name="ostmp" type="radio" value="" onclick="osdo('asp+sql/access')" /> asp+sql/access <strong>php源碼</strong> <input name="ostmp" type="radio" value="" onclick="osdo('php')" />php <input name="ostmp" type="radio" value="" onclick="osdo('php+mysql')" /> php+mysql<input name="ostmp" type="radio" value="" onclick="osdo('jsp')" />jsp <strong>asp.net源碼</strong> <input name="ostmp" type="radio" value="" onclick="osdo('asp.net')" />asp.net <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+access')" />asp.net+access <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+sql')" />asp.net+sql <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+sql/access')" />asp.net+sql/access

[Ctrl+A 全選注:如需引入外部Js需刷新才能執行]

可以看到這段代碼在ie7與ie8中都是可以運行的，下面的代碼我們加入聲明文檔

復制代碼代碼如下:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 

加了上面的文檔類型聲明。

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 運行環境： <input type='text' name='os' value='Windows平臺' style='width:100px' /> <script type="text/javascript">                 function osdo(str){                 document.getElementById("os").value=str;                 }                 </script> <input name="ostmp" type="radio" value="" onclick="osdo('')" />清空 <input name="ostmp" type="radio" value="Windows平臺" onclick="osdo('Windows平臺')" /> Windows平臺 <input name="ostmp" type="radio" value="" onclick="osdo('S60v2')" />S60v2 <input name="ostmp" type="radio" value="" onclick="osdo('S60v3')" />S60v3 <input name="ostmp" type="radio" value="" onclick="osdo('CHM')" />CHM <input name="ostmp" type="radio" value="" onclick="osdo('PDF')" />PDF <input name="ostmp" type="radio" value="" onclick="osdo('PPT')" />PPT <input name="ostmp" type="radio" value="" onclick="osdo('DOC')" />WORD <input name="ostmp" type="radio" value="" onclick="osdo('EXCEL')" />EXCEL <input name="ostmp" type="radio" value="" onclick="osdo('asp')" />asp <input name="ostmp" type="radio" value="" onclick="osdo('asp+access')" />asp+access <input name="ostmp" type="radio" value="" onclick="osdo('asp+sqlserver')" />asp+sqlserver <input name="ostmp" type="radio" value="" onclick="osdo('asp+sql/access')" /> asp+sql/access <strong>php源碼</strong> <input name="ostmp" type="radio" value="" onclick="osdo('php')" />php <input name="ostmp" type="radio" value="" onclick="osdo('php+mysql')" /> php+mysql<input name="ostmp" type="radio" value="" onclick="osdo('jsp')" />jsp <strong>asp.net源碼</strong> <input name="ostmp" type="radio" value="" onclick="osdo('asp.net')" />asp.net <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+access')" />asp.net+access <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+sql')" />asp.net+sql <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+sql/access')" />asp.net+sql/access

[Ctrl+A 全選注:如需引入外部Js需刷新才能執行]

發現提示document.getElementById(...) 為空或不是對象的解決方法
如果頁面中既有文檔聲明，因為用div+css布局的時候，聲不聲明文檔，頁面的一些地方都不一樣。
可以在head中添加下面的代碼

復制代碼代碼如下:

完整的代碼

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <meta http-equiv="X-UA-Compatible" content="IE=EmulateIE7" /> 運行環境： <input type='text' name='os' value='Windows平臺' style='width:100px' /> <script type="text/javascript">                 function osdo(str){                 document.getElementById("os").value=str;                 }                 </script> <input name="ostmp" type="radio" value="" onclick="osdo('')" />清空 <input name="ostmp" type="radio" value="Windows平臺" onclick="osdo('Windows平臺')" /> Windows平臺 <input name="ostmp" type="radio" value="" onclick="osdo('S60v2')" />S60v2 <input name="ostmp" type="radio" value="" onclick="osdo('S60v3')" />S60v3 <input name="ostmp" type="radio" value="" onclick="osdo('CHM')" />CHM <input name="ostmp" type="radio" value="" onclick="osdo('PDF')" />PDF <input name="ostmp" type="radio" value="" onclick="osdo('PPT')" />PPT <input name="ostmp" type="radio" value="" onclick="osdo('DOC')" />WORD <input name="ostmp" type="radio" value="" onclick="osdo('EXCEL')" />EXCEL <input name="ostmp" type="radio" value="" onclick="osdo('asp')" />asp <input name="ostmp" type="radio" value="" onclick="osdo('asp+access')" />asp+access <input name="ostmp" type="radio" value="" onclick="osdo('asp+sqlserver')" />asp+sqlserver <input name="ostmp" type="radio" value="" onclick="osdo('asp+sql/access')" /> asp+sql/access <strong>php源碼</strong> <input name="ostmp" type="radio" value="" onclick="osdo('php')" />php <input name="ostmp" type="radio" value="" onclick="osdo('php+mysql')" /> php+mysql<input name="ostmp" type="radio" value="" onclick="osdo('jsp')" />jsp <strong>asp.net源碼</strong> <input name="ostmp" type="radio" value="" onclick="osdo('asp.net')" />asp.net <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+access')" />asp.net+access <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+sql')" />asp.net+sql <input name="ostmp" type="radio" value="" onclick="osdo('asp.net+sql/access')" />asp.net+sql/access

[Ctrl+A 全選注:如需引入外部Js需刷新才能執行]

上一篇：js鼠標移動在title中顯示圖片的效果代碼

下一篇：javascript &&和||運算法的另類使用技巧