当我尝试上传图像 ASP.NET 时，图像是 NULL

Question

• 设置一个表单，用户可以在其中填写他们必须上传图像的表单。

代码：

string FileName = Path.GetFileNameWithoutExtension(customerImage.ImageFile.FileName);

string FileExtension = Path.GetExtension(customerImage.ImageFile.FileName);

FileName = DateTime.Now.ToString("yyyyMMdd") + "-" + FileName.Trim() + FileExtension;

string UploadPath = ConfigurationManager.AppSettings["UserImagePath"].ToString();

customerImage.Image = UploadPath + FileName;

customerImage.ImageFile.SaveAs(customerImage.Image);

有问题的线路：

string FileName = Path.GetFileNameWithoutExtension(customerImage.ImageFile.FileName);

错误：上传图片错误

请帮助我是一名大学生，这是一个最终项目：（（（（（（（（（（（）

Answer 1

您有一个 object 引用错误（空引用异常），很可能是文件上传控件没有正确初始化或者在向服务器端发送请求时没有文件附加到控件。

如果 customerImage 是 ASP 文件上传控件，您可以访问文件名，如下所示：

FileUpload1.FileName

请参阅以下示例：对于 HTML

<asp:FileUpload ID="FileUpload1" runat="server" />  
<asp:Button ID="Button1" runat="server" Text="Upload" onclick="Button1_Click"/>  
<br />  
<asp:Image ID="Image1" runat="server" />  

服务器端

protected void Button1_Click(object sender, EventArgs e) {  
             StartUpLoad();  
}  
     
private void StartUpLoad() {  
        //get the file name of the posted image  
        string imgName = FileUpload1.FileName;  
        //sets the image path  
        string imgPath = "ImageStorage/" + imgName;            
       //get the size in bytes that  
  
       int imgSize = FileUpload1.PostedFile.ContentLength;  
      
       //validates the posted file before saving  
        if (FileUpload1.PostedFile != null && FileUpload1.PostedFile.FileName != "") {  
           // 10240 KB means 10MB, You can change the value based on your requirement  
                if (FileUpload1.PostedFile.ContentLength > 10240) {  
                           Page.ClientScript.RegisterClientScriptBlock(typeof(Page), "Alert", "alert('File is too big.')", true);  
                 }  else {  
                           //then save it to the Folder  
                           FileUpload1.SaveAs(Server.MapPath(imgPath));  
                           Image1.ImageUrl = "~/" + imgPath;  
                           Page.ClientScript.RegisterClientScriptBlock(typeof(Page), "Alert", "alert('Image saved!')", true);  
                }  
    
          }  
}  

试试这个，看看你的代码有什么问题。