Monday, November 26, 2012

Asp.net validation add text background color

Following is code for adding background color to the text box if validation fails in asp.net web form-

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <asp:TextBox ID="txtOne" runat="server" />
      <asp:RequiredFieldValidator ID="rfv" runat="server" 
                                 ControlToValidate="txtOne" Text="" />
      <asp:TextBox ID="txtTwo" runat="server" />
      <asp:RequiredFieldValidator ID="rfv2" runat="server" 
                                 ControlToValidate="txtTwo" Text="" />
      <asp:Button ID="btnOne" runat="server" OnClientClick="return BtnClick();" 
                                         Text="Click" CausesValidation="true" />
   <script type="text/javascript">
       function BtnClick() {
            var val = Page_ClientValidate();
            if (!val) {
                var i = 0;
                for (; i < Page_Validators.length; i++) {
                    if (!Page_Validators[i].isvalid) {
                        $("#" + Page_Validators[i].controltovalidate)
                         .css("background-color", "red");
                    }
                }
            }
            return val;
        }
    </script>
    </form>
</body>
</html>


Wednesday, November 7, 2012

Export PDF using jQuery and generic handler in asp.net

Recently I have added a post regarding Export HTML to excel using jQuery and asp.net. Here I am repeating the same for PDF. I will suggest you to go through the previous post as I am not explaining repeating technical aspects.

Let’s directly check the following HTML code-
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.7.js" type="text/javascript"></script>
<script type="text/javascript">
    $(document).ready(function() { 
        $(".expPDF").click(function(){
            var someDummyParameter="test";
            $('body').prepend("<form method='post' action='GetPDF.ashx' style='top:-3333333333px;' id='tempForm'><input type='hidden' name='data' value='" + someDummyParameter + "' ></form>");
            $('#tempForm').submit();
            $("tempForm").remove();
        });
    });
</script>
</head>
<body>
    <form id="form1" runat="server">
    <a href="#" target="_blank" class="expPDF">Export to pdf</a>
    </form>
</body>
</html>
The above code is simple. We are having a simple anchor(a) as a button to lunch the PDF. On the click of the anchor we are creating a form tag on the fly, assigning the action to a generic handler that will create the PDF file. At the end we are submitting the form. On the form submit the form will get posted to generic handler. In this example we are also passing some dummy data as hidden filed which will be accessible in the handler code. Likewise we need some additional information we can pass form elements.

Now let’s define the handler code. In the handler we can create the PDF file using some library like itextsharp or something similar. But in this example we are just reading PDF file from the memory the memory. Code is like this-
<%@ WebHandler Language="C#" Class="GetPDF" %>

using System;
using System.Web;

public class GetPDF : IHttpHandler {
    
    public void ProcessRequest (HttpContext context) {
                
        string inputData = context.Request.Form["data"];
        
        byte[] buffer;
        using (System.IO.FileStream fileStream = new System.IO.FileStream(@"E:\ForumPosts\jQueryPDF\" + inputData + ".pdf", System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read))
        using (System.IO.BinaryReader reader = new System.IO.BinaryReader(fileStream))
        {
            buffer = reader.ReadBytes((int)reader.BaseStream.Length);
        }
        context.Response.ContentType = "application/pdf";
        context.Response.AddHeader("Content-Length", buffer.Length.ToString());
        context.Response.AppendHeader("content-disposition", "inline; filename=test.pdf"); 
        context.Response.BinaryWrite(buffer);
        context.Response.End(); 
    }
 
    public bool IsReusable {
        get {
            return false;
        }
    }

}
As you can see the first line in the handler ProcessRequest function we are accessing the form data passed string inputData = context.Request.Form["data"];. The remaining code is self-explanatory. The PDF file path I have hard coded according to my folder structure.

You can download the code form here.