Question

我有简单的asp.net异步上传，我试图从本地系统上传样本图像，并在上传时尝试执行简单的web方法。

Scenanrio：

使用异步上传器上传图片并将其正常工作并将其上传到dest文件夹。
现在尝试在隐藏字段中保存fileupload.filename并测试它是否真正获取文件名（这也有效）
现在尝试发送保存隐藏字段值的var时出现了问题。这里显示我是未定义的。

这是我的代码：

Protected Sub fileUploadComplete(ByVal sender As Object, ByVal e As AsyncFileUploadEventArgs)
    Thread.Sleep(1000)
    Dim filename As String = System.IO.Path.GetFileName(fileUpload1.FileName)
    fileUpload1.SaveAs(Server.MapPath("UploadFiles/") & RandomFolder.Value & "/" & filename)
    lblFilename.Value = filename
End Sub

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not IsPostBack Then
        CreateFolder()
    End If
    Dim mypath As String = Server.MapPath("~/UploadFiles/")
    myFilePath.Value = mypath

End Sub
<WebMethod()> _

公共函数FileDetails（ByVal Filename As String，ByVal mypath As String）As String //一些操作返回“真实” 结束功能

HTML：

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
           <link href="style/bootstrap.css" rel="stylesheet" />
    <script src="http://code.jquery.com/jquery-1.11.0.min.js"></script>
<script type="text/javascript">
    // This function will execute after file uploaded successfully
    function uploadComplete() {
        document.getElementById('<%=lblMsg.ClientID %>').innerHTML = "File Uploaded Successfully";
}
// This function will execute if file upload fails
function uploadError() {
    document.getElementById('<%=lblMsg.ClientID %>').innerHTML = "File upload Failed.";
}

$(document).ready(function () {
    $("#btnconvert").click(function () {
        var FileFolder = $('#RandomFolder').val();
        var filename = document.getElementById('<%=lblFilename.ClientID %>').val();
        alert(FileFolder);
        alert(filename);
        $.ajax({
            type: "POST",
            url: "AsyncUpload.aspx/FileDetails",
            data: JSON.stringify('{"Filename":"' + filename + '","mypath":"' + FileFolder + '"}'),
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (msg) {
                // Replace the div's content with the page method's return.
                alert("Success");
            }
        });
    });
});
</script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <asp:ToolkitScriptManager ID="scriptManager1" runat="server"/>
<div>
<asp:AsyncFileUpload ID="fileUpload1" OnClientUploadComplete="uploadComplete" OnClientUploadError="uploadError" 
CompleteBackColor="White" Width="350px" runat="server" UploaderStyle="Modern" UploadingBackColor="#CCFFFF" 
ThrobberID="imgLoad" OnUploadedComplete="fileUploadComplete" /><br />
<asp:Image ID="imgLoad" runat="server" ImageUrl="loading.gif" />
<br />
<asp:Label ID="lblMsg" runat="server" Text=""></asp:Label>
</div>
    <asp:HiddenField ID="RandomFolder" runat="server"/>
    <asp:HiddenField ID="FilePath" runat="server"/>
     <asp:HiddenField ID="myFilePath" runat="server"/>
     <asp:HiddenField ID="lblFilename" runat="server"/>
     <button id="btndetails" class="btn btn-danger btnconvert" type="button">Convert file</button>
    </div>

Answer 1

您使用val（）方法调用隐藏字段的值，但该字段对象上不存在该方法;它是一个jQuery方法。将您隐藏的字段包装在jQuery中：

var filename = $('#<%=lblFilename.ClientID %>').val();

或者只是在你的字段上调用.value属性：

var filename = document.getElementById('<%=lblFilename.ClientID %>').value;

Answer 2

请参阅此page它可以帮助您实现正在尝试的目标

隐藏字段值显示未定义

2 个答案: