php js实现图片上传预览
图片裁剪,预览,上传保存的功能。这个功能一般用于会员中心的图片。
下面代码为js实现图片上传预览```javascript
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<input type=file name="doc" id="doc" onchange="javascript:setImagePreview();">
<p>
<div id="localImag"><img id="preview" width=-1 height=-1 style="diplay:none" /></div>
</p>
<script>
function setImagePreview() {
var docObj=document.getElementById("doc");
var imgObjPreview=document.getElementById("preview");
if(docObj.files && docObj.files[0]){
//火狐下,直接设img属性
imgObjPreview.style.display = 'block';
imgObjPreview.style.width = '300px';
imgObjPreview.style.height = '120px';
//imgObjPreview.src = docObj.files[0].getAsDataURL();
//火狐7以上版本不能用上面的getAsDataURL()方式获取,需要一下方式
imgObjPreview.src = window.URL.createObjectURL(docObj.files[0]);
}else{
//IE下,使用滤镜
docObj.select();
var imgSrc = document.selection.createRange().text;
var localImagId = document.getElementById("localImag");
//必须设置初始大小
localImagId.style.width = "300px";
localImagId.style.height = "120px";
//图片异常的捕捉,防止用户修改后缀来伪造图片
try{
localImagId.style.filter="progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)";
localImagId.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = imgSrc;
}catch(e){
alert("");
return false;
}
imgObjPreview.style.display = 'none';
document.selection.empty();
}
return true;
}
</script>
</body>
</html>
php上传缩略图 ```php <form method="post" action="suo_do.php" enctype="multipart/form-data"> <input type="file" name="pic" /> <input type="submit" value="上传1" /> </form> <?php header("content-type:text/html;charset=gbk"); ini_set("date.timezone","Asia/chong"); //判断文件是否为空 if(empty($_FILES)){ echo"上传文件过大"; exit; } //判断文件上传是否有错误 if($_FILES['pic']['error']){ echo "上传文件"; exit; } //判断文件类型是否非法获取文件后缀 $allowtype=array("jpg","png","jpeg","gif"); $a=explode('.',$_FILES['pic']['name']); $index=count($a)-1; $ex=strtolower($a[$index]); if(!in_array($ex,$allowtype)){ echo "上传文件非法"; exit; } $file=date('YmdHis').rand().".".$ex; $src=$_FILES['pic']['tmp_name']; $des="upload/".$file; $rs=move_uploaded_file($src,$des); //缩略图 //读取已经上传图片 $image=imagecreatefromjpeg($des); $a=getimagesize($des); $w=$a[0]; $h=$a[1]; if($w>$h){ $width=300; $height=$width/$w*$h; }else if($w<$h){ $height=300; $width=$height/$h*$w; }else{ $width=300; $height=300; } //创建空白新图片 $newimage=imagecreatetruecolor($width, $height); //copy源图片内容 copy新图片 imagecopyresized($newimage, $image, 0,0, 0,0, $width, $height, $w, $h); $filename="upload/s_".$file; imagejpeg($newimage,$filename);