在asp.net中验证错误后，Page.IsValid始终为false

Question

i have a code to file upload ... in onchange event checking file size , format before uploading to physical folder. if all validation are true then Upload button will be triggered from onchange event.

Everything working fine but i upload wrong format file and validation error will popup and in next file upload Page.Isvalid is false so file not uploading even the correct format/size is uploaded. how to solve this issue.

below is the code:

javascript

 function UploadFile(fileUpload) {


    if (fileUpload.value != '') {
        var title = document.getElementById("<%=txtTitle.ClientID%>").value;
        var sFileName = fileUpload.value.toLowerCase();
        var sFileExtension = sFileName.split('.')[sFileName.split('.').length - 1];
        var file = (fileUpload.files[0].size / 1024);
        var limit = <%= ConfigurationManager.AppSettings["MaxLimit"]%>;

        var maxlimit = limit * 1024;
        var type = document.getElementById("<%=hdnType.ClientID%>").value;
        if (title != "") {
            if (file > maxlimit) {


                fileUpload.value = null;
                ShowAlert("Sorry the file you are trying to upload exceeds the allowed file limit. Allowed size is 10MB.");

            }
            else {
                if (type == 1) {
                    if (sFileExtension != "png" && sFileExtension != "jpg" && sFileExtension != "jpeg") {

                        fileUpload.value = null;
                        ShowAlert("File Format not supported. Please upload .jpeg/.png files");


                    }
                    else {
                        document.getElementById("<%=btnSave.ClientID%>").click();

                    }
                }
}
}


 <asp:FileUpload ID="upldfile" runat="server" onchange="UploadFile(this)"  ClientIDMode="Static" />
 <asp:Button ID="btnSave" runat="server" UseSubmitBehavior="false" ValidationGroup="save" Text="Save" style="display:none;" OnClick="Upload"  data-dismiss="modal"   class="btn btn-danger" />

Upload event

 public void Upload(object sender, EventArgs e)
    {
        if (Page.IsValid)
        {
            SavePortfolio();
        }


    }

Answer 1

Try this

function UploadFile(fileUpload) 
{
    if (fileUpload.value != '') {
        var title = document.getElementById("<%=txtTitle.ClientID%>").value;
        var sFileName = fileUpload.value.toLowerCase();
        var sFileExtension = sFileName.split('.')[sFileName.split('.').length - 1];
        var file = (fileUpload.files[0].size / 1024);
        var limit = <%= ConfigurationManager.AppSettings["MaxLimit"]%>;
        var maxlimit = limit * 1024;
        var type = document.getElementById("<%=hdnType.ClientID%>").value;

        if (title != "") {
            if (file > maxlimit) {
                fileUpload.value = null;
                ShowAlert("Sorry the file you are trying to upload exceeds the allowed file limit. Allowed size is 10MB.");
                return;
            }
            else {
                if (type == 1) {
                    if (sFileExtension != "png" && sFileExtension != "jpg" && sFileExtension != "jpeg") {
                        fileUpload.value = null;
                        ShowAlert("File Format not supported. Please upload .jpeg/.png files");
                        return;
                    }
                    else {
                        document.getElementById("<%=btnSave.ClientID%>").click();
                    }
                }
            }
        }
    }
}