OnClick button working only after second time Asp.NET c#
Question
I'm new to web development and right now I'm working on a website. I have a problem with a Save button on an ASP.Net (front end) web form (back end is in C#). The button is supposed to save data entered in a textbox to a database.
When the Save button is clicked the first time, the page just 'reloads' and clear the textbox and nothing is saved in the SQL Server database (dbo connection). Then when I click the same 'Save' button a second time after re-entering information in the textbox, it actually saves to the database and goes back to a main menu page (as expected). And if I try to re-enter different information, the save button will be working just fine.
The problem happens when a user logs in and navigate to the page where he enters the data and saves it. It will never ever work the first time.
Unfortunately because of confidential purposes, I have to omit and rename certain file paths/directories and tables name!
Here's my Asp.NET code:
<%@ Page Language="C#" debug="True" Inherits="Default" src="Default.cs" AutoEventWireup ="true"%>
<%@ Register TagPrefix="ob" TagName="ComboTree" Src="/obout/Combotree/ComboTree.ascx" %>
<%@ Reference Control="/obout/Combotree/ComboTree.ascx" %>
<HTML>
<HEAD>
<!-- #INCLUDE VIRTUAL="/.../" -->
</HEAD>
<BODY >
<FORM runat="server">
<BASEFONT face="Arial, Helvetica, Sans Serif" color=black size=2>
<TABLE height="100%" cellSpacing=0 cellPadding=0 width="780" align=Center border=0>
<!-- #INCLUDE VIRTUAL="/.../" -->
<TR VALIGN="top">
<!-- #INCLUDE VIRTUAL="/.../" -->
`enter code here`<TD vAlign=top width="100%" HEIGHT="100%">
<TABLE cellSpacing=0 cellPadding=0 width="100%" border=0 HEIGHT="100%">
<!-- #INCLUDE VIRTUAL="/.../" -->
<TR>
<!-- #INCLUDE VIRTUAL="/.../" -->
<TD vAlign=top align=left >
<!--- START YOUR CODE HERE!!!!! --->
<script>
function disableListItems(checkBoxListId, disable)
{
// Get the checkboxlist object.
ctr = 0;
while(1 == 1)
{
checkbox = document.getElementById(checkBoxListId + "_" + ctr);
if(checkbox == null)
{
return;
}
checkbox.checked = true;
checkbox.disabled = disable;
ctr++;
}
}
function checkForm()
{
var errMsg = "";
if(isBlank(document.getElementById("tbName").value))
{
errMsg += "\n-Folder Name";
}
if(errMsg!="")
{
alert("The following fields cannot be left blank." + errMsg);
return false;
}
return true;
}
</script>
<font Class="heading">File Library - <ASP:Label ID="lbTitle" RunAt="Server"/> Folder</font>
<INPUT Type="Hidden" ID="hdFolderID" RunAt="Server"/>
<INPUT Type="Hidden" ID="hdParentFolderID" RunAt="Server"/>
<TABLE CellPadding="4" CellSpacing="0" Width="100%" >
<TR>
<TD ColSpan="2" Class="spreadsheet_line"> </TD>
</TR>
<TR>
<TD Class="Spreadsheet"><B>Name</B></TD>
<TD Class="Spreadsheet" Width="100%"><ASP:TextBox ID="tbName" Columns="34" RunAt="Server"/></TD>
</TR>
<TR VAlign="Top" Visible="False" RunAt="Server">
<TD Class="Spreadsheet" NOWRAP><B>Description</B></TD>
<TD Class="Spreadsheet"><ASP:TextBox ID="tbDescription" TextMode="Multiline" Cols="25" Rows="5" RunAt="Server"/></TD>
</TR>
<TR>
<TD Class="Spreadsheet"><B>Active?</B></TD>
<TD Class="Spreadsheet"><ASP:CheckBox ID="cbActive" RunAt="Server"/></TD>
</TR>
<TR Visible="False" RunAt="Server">
<TD Class="Spreadsheet"><B>Folder</B></TD>
<TD Class="Spreadsheet"><ob:ComboTree id="ctFolders" runat="server"/></TD>
</TR>
<TR VAlign="Top" ID="trLicensees" RunAt="Server">
<TD Class="Spreadsheet"><B>Departments</B></TD>
<TD Class="Spreadsheet">
<ASP:DropDownList ID="ddLicensee" DataTextField="Name" DataValueField="DepartmentId" RunAt="Server"/>
<ASP:CheckBox ID="cbAll" Text="All" RunAt="Server"/>
<div style="text-align: left; width: 30%; margin-left:-3px">
<ASP:CheckBoxList ID="cblLicensees" DataTextField="Name" DataValueField="DepartmentId" style="background-color:F3F3F3" RunAt="Server"/> <!--**-->
</div>
</TD>
</TR>
<TR>
<TD Class="Spreadsheet" Align="Right" ColSpan="2">
<ASP:ImageButton ID="btnSave" OnClick="btnSave_OnClick" ImageUrl="/images/buttons/btnSave.gif" RunAt="Server"/>
</TD>
</TR>
</TABLE>
<!--- END YOUR CODE HERE!!!!! --->
</TD>
<!-- #INCLUDE VIRTUAL="/.../" -->
</TR>
<!-- #INCLUDE VIRTUAL="/.../" -->
</TABLE>
</TD>
<!-- #INCLUDE VIRTUAL="/.../" -->
</TR>
<!-- #INCLUDE VIRTUAL="/.../" -->
</TABLE>
</BASEFONT>
</FORM>
</BODY>
</HTML>
And here's the (back end) code for the Save button written in C#:
public void btnSave_OnClick(object sender, System.Web.UI.ImageClickEventArgs E){
int counter = int.Parse(Request.Cookies["counter"].Value);
counter++;
Response.Cookies["counter"].Value = counter.ToString();
try{
SqlConnection Conn = GetConnection();
string SQL;
SqlCommand Cmd;
SqlDataReader Dtr;
if(hdFileID.Value=="")
{
Response.Write("Executing Save (adding new folder to DB");
SQL = "EXEC sp_File_Add @Name,@Description,@UserID";
Response.Write("Save successfully executed. Added to DB");
}
else
{
Response.Write("Executing Save (saving info of folder to DB");
SQL = "EXEC sp_File_Update @Name,@Description,@UserID,@FileID";
Response.Write("Save successfully executed. Saved to DB");
}
Cmd = new SqlCommand(SQL,Conn);
Cmd.Parameters.Add(new SqlParameter("@Name", SqlDbType.VarChar));
Cmd.Parameters["@Name"].Value = tbName.Text;
Cmd.Parameters.Add(new SqlParameter("@Description", SqlDbType.Text));
Cmd.Parameters["@Description"].Value = tbDescription.Text;
Cmd.Parameters.Add(new SqlParameter("@UserID", SqlDbType.Int));
Cmd.Parameters["@UserID"].Value = Convert.ToInt32(hdUserID_Global.Value);
if(hdFileID.Value!="")
{
Cmd.Parameters.Add(new SqlParameter("@FileID", SqlDbType.Int));
Cmd.Parameters["@FileID"].Value = Convert.ToInt32(hdFolderID.Value);
}
Cmd.ExecuteNonQuery();
if(hdFileID.Value=="")
{
SQL = "SELECT MAX(FileID) AS FileID FROM tbl_File WHERE CreatedByUserID=@UserID";
Cmd = new SqlCommand(SQL,Conn);
Cmd.Parameters.Add(new SqlParameter("@UserID", SqlDbType.Int));
Cmd.Parameters["@UserID"].Value = Convert.ToInt32(hdUserID_Global.Value);
Dtr = Cmd.ExecuteReader();
if(Dtr.Read())
{
hdFileID.Value = Dtr["FileID"].ToString();
}
Dtr.Close();
}
SQL = "DELETE FROM tbl_FileLicense ";
SQL += " WHERE FileID=@FileID ";
Cmd = new SqlCommand(SQL,Conn);
Cmd.Parameters.Add(new SqlParameter("@FileID", SqlDbType.Int));
Cmd.Parameters["@FileID"].Value = Convert.ToInt32(hdFileID.Value.ToString());
Cmd.ExecuteNonQuery();
if(ddLicense.Visible)
{
SQL = "EXEC sp_doc_Folder_Add @FileID,@LicenseID,@UserID";
Response.Write("Save successfully executed. Added to DB");
Cmd = new SqlCommand(SQL,Conn);
Cmd.Parameters.Add(new SqlParameter("@FolderID", SqlDbType.Int));
Cmd.Parameters["@FileID"].Value = Convert.ToInt32(hdFileID.Value.ToString());
Cmd.Parameters.Add(new SqlParameter("@LicenseID", SqlDbType.Int));
Cmd.Parameters["@LicenseID"].Value = Convert.ToInt32(ddLicense.SelectedItem.Value.ToString());
Cmd.Parameters.Add(new SqlParameter("@UserID", SqlDbType.Int));
Cmd.Parameters["@UserID"].Value = Convert.ToInt32(hdUserID_Global.Value);
Cmd.ExecuteNonQuery();
}
else
{
}
Conn.Close();
Response.Redirect("/Library/Default2.aspx?FileID=" + Request["RootFileID"].ToString());
Response.End();
}
catch (Exception e){
Response.Write("An error occurred while saving: " + e);
Response.End();
}
}
I've been struggling for more than 2 days on that and I don't see why the button is not firing the first time but only as from the 2nd time. Any help will be greatly appreciated. Thank you.
2 answers
solution1
0 2016-06-08 04:20:37
You should open connection ie Conn.open() before executing cmd.ExecuteNonQuery() method.
Try this, if it still doesn't work, in first line of webform.aspx ie <%@ Page Language="C#" add this attribute and see if it works: EnableEventValidation="false" . Also check the flow of code by setting breakpoints.
solution2
0 ACCPTED 2016-06-13 17:28:19
我通过在asp.NET代码中的<FORM runat="server">标记中添加EnableViewState = False来实现它
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