ajax上传文件

前端示例：

<input type="file" name="fileName" id="fileName" />

<input id="import" type="button" value="导入" onclick="uploadFile()" >

js：

function uploadFile()
{
var formData = new FormData();
formData.append("myfile",document.getElementById("fileName").files[0]);
$.ajax({
url: "ComplainStatisticsAnalyze.ashx?Method=uploadFile",
type: "POST",
data: formData,
/**
*必须false才会自动加上正确的Content-Type
*/
contentType: false,
/**
* 必须false才会避开jQuery对 formdata 的默认处理
* XMLHttpRequest会对 formdata 进行正确的处理
*/
dataType: "text",
processData: false,
success: function (data) {
alert(data);
},
error: function (XMLHttpRequest,textStatus,errorThrown) {
alert("数据导入异常：" + errorThrown);
}
});
}

后台示例：

public string uploadFile(HttpContext context) { string result = ""; context.Response.ContentType = "text/html"; HttpPostedFile file = null; try { if (context.Request.Files.Count > 0) { file = context.Request.Files["myfile"]; } else { return "请选择要上传的文件"; } string oldfileName = Path.GetFileName(file.FileName); //获得文件名+拓展名 string fileExt = Path.GetExtension(oldfileName); //获得拓展名 string IsXls = Path.GetExtension(file.FileName).ToString().ToLower();//System.IO.Path.GetExtension获得文件的扩展名 if (IsXls != ".xlsx" && IsXls != ".xls") { return "文件类型不正确"; } else { string savePath = context.Server.MapPath(("UploadImportExcel") + oldfileName); file.SaveAs(savePath); } } catch (Exception ex) {　　? throw ex; } return result; }