<div class="container"><!--读取要上传的文件--><input type="file" id="file"  /><input type="button" id="btn1" value="点击上传" onclick="uploadClick();" />
</div>

//读取图片实例,并上传到服务器
var fileBox = document.getElementById('file');
fileBox.onchange = function () {//获取选择文件的数组var fileList = fileBox.files;for (var i = 0; i < fileList.length; i++) {var file = fileList[i];uploadFile(file);}
}
//关键代码上传到服务器
function uploadFile(file) {var reader = new FileReader();reader.readAsArrayBuffer(file);reader.onload = function () {var blob = new Blob([reader.result]);//提交到服务器var fd = new FormData();fd.append('file', blob);var ext = file.name.substring(file.name.lastIndexOf('.'));fd.append('extention', ext);fd.append('maxsize', 1024*1024*4);//Asp.net 默认一次上传最大4MBfd.append('isClip', -1);var xhr = new XMLHttpRequest();xhr.open('post', '../ashx/upload.ashx', true);xhr.onreadystatechange = function () {if (xhr.readyState == 4 && xhr.status == 200) {var data = eval('(' + xhr.responseText + ')');console.info(data);if (data.success) {//上传成功var imgName = data.msg;alert(imgName);} else {alert(data.msg);}}}//开始发送
        xhr.send(fd);}
}

//接收文件
HttpRequest req = _Context.Request;
string newname = _fileInfo.CreateNewName(newExtention);
//接收二级制数据并保存
Stream stream = _PostedFile.InputStream;
byte[] dataOne = new byte[stream.Length];
stream.Read(dataOne, 0, dataOne.Length);
FileStream fs = new FileStream(_fileInfo.TempFile + newname, FileMode.Create, FileAccess.Write);
try
{fs.Write(dataOne, 0, dataOne.Length);
}
finally
{fs.Close();stream.Close();
}
return newname;

<div class="container"><!--图片类型验证方法1--><input type="file" id="file" accept="image/*" /><input type="button" id="btn1" value="点击上传" onclick="uploadClick();" /><h4>选择文件如下:</h4><img src="" id="img1" />
</div>

//读取图片实例,并上传到服务器
var fileBox = document.getElementById('file');
fileBox.onchange = function () {//获取选择文件的数组var fileList = fileBox.files;for (var i = 0; i < fileList.length; i++) {var file = fileList[i];//图片类型验证第二种方式if (/image\/\w+/.test(file.type))readFile(file);elseconsole.log(file.name + ':不是图片');}
}
//读取二进制图片文件，并上传到服务器
function uploadClick() {var fileList = fileBox.files;for (var i = 0; i < fileList.length; i++) {var file = fileList[i];//图片类型验证第二种方式if (/image\/\w+/.test(file.type))uploadFile(file);elseconsole.log(file.name + ':不是图片');}
}
//关键代码上传到服务器
function uploadFile(file) {var reader = new FileReader();reader.readAsArrayBuffer(file);reader.onload = function () {var blob = new Blob([reader.result], { type: 'image/jpg' });//提交到服务器var fd = new FormData();fd.append('file', blob);var ext = file.name.substring(file.name.lastIndexOf('.'));fd.append('extention', ext);fd.append('isClip', -1);var xhr = new XMLHttpRequest();xhr.open('post', '../ashx/upload.ashx', true);xhr.onreadystatechange = function () {if (xhr.readyState == 4 && xhr.status == 200) {var data = eval('(' + xhr.responseText + ')');console.info(data);if (data.success) {//上传成功var imgName = data.msg;alert(imgName);} else {alert(data.msg);}}}//开始发送
        xhr.send(fd);}
}
//读取图片内容 为DataURL
function readFile(file) {var reader = new FileReader();reader.readAsDataURL(file);reader.onload = function (e) {var result = reader.result;$('.container blockquote').text(result);$('#img1').attr('src', result)}
}