javascript 保存文件到本地实现方法

2种形式都可以
第一种：

<script> 
function SaveAs5(imgURL) 
{ 
var oPop = window.open(imgURL,"","width=1, height=1, top=5000, left=5000"); 
for(; oPop.document.readyState != "complete"; ) 
{ 
if (oPop.document.readyState == "complete")break; 
} 
oPop.document.execCommand("SaveAs"); 
oPop.close(); 
} 
</script> 
<img src="t_screenshot_17616.jpg" id="DemoImg" border="0" onclick="SaveAs5(this.src)">

第二种：

<script> 
function SaveAs5(imgURL) 
{ 
var oPop = window.open(imgURL,"","width=1, height=1, top=5000, left=5000"); 
for(; oPop.document.readyState != "complete"; ) 
{ 
if (oPop.document.readyState == "complete")break; 
} 
oPop.document.execCommand("SaveAs"); 
oPop.close(); 
} 
</script> 
<img src="../t_screenshot_17616.jpg" id="DemoImg" border="0"> 
<a href="#" onclick="SaveAs5(document.getElementById('DemoImg').src)"> 点击这里下载图片 </a>