React-select is very slow on larger list - Found solution - using react-window

 I had more than 4000 items in searchable dropdownlist. I have used react-select but it was very slow. finally I found complete solution to make it fast. Faster solution for large data is here: see below:

import { FixedSizeList as List } from 'react-window';

import Select, { createFilter } from 'react-select';

<Select 
                        value={this.state.selectedReport}
                        onChange={this.handleChangeReport}
                        filterOption={createFilter({ ignoreAccents: false })} // this makes it fast!
                        components={{ CustomMenu }}
                        options={Reports}
                        isClearable={true}

                    />



const CustomMenu = props => {
            
            const { Reports, children, maxHeight, getValue } = this.props;
            const [value] = getValue();


            return (
                <List
                    height={150}
                    itemCount={children.length}
                    itemSize={35}
                >
                    {({ index, style }) => <div style={style}>{children[index]}</div>}
                </List>
            );
        };

React - axios api call to render file using blob - pdf or excel or xls or xlsx - using Asp.net

 I was struggling to call API to get PDF/Excel files. I found complete solution which is working in all browsers. Here is the .net c# code:

[Route("api/queries")]
    [HttpGet]
    public string getFile()
    {
        WebClient Client = new WebClient();
        Client.UseDefaultCredentials = true;
        byte[] myDataBuffer = Client.DownloadData("URL");
        string DocumentPath = Convert.ToBase64String(myDataBuffer);
        return DocumentPath;
    }

And here is front end in React using axios and blob:

axios.get(fetchFileUrl)
            .then((response) => {
                var raw = window.atob(response.data);
                var uint8Array = new Uint8Array(raw.length);
                for (var i = 0; i < raw.length; i++) {
                    uint8Array[i] = raw.charCodeAt(i);
                }
                var newBlob = new Blob([uint8Array])
                if (window.navigator && window.navigator.msSaveOrOpenBlob) {
                    window.navigator.msSaveOrOpenBlob(newBlob, fileName + '.xlsx');
                    console.log('ie', '11');
                }
                else {
                    const data = window.URL.createObjectURL(newBlob);
                    var link = document.createElement('a');
                    link.href = data;
                    link.download = fileName + '.xlsx';
                    link.click();
                    link.remove();
                    setTimeout(function () {
                        // For Firefox it is necessary to delay revoking the ObjectURL
                        window.URL.revokeObjectURL(data);
                    }, 100);
                    
                    console.log('not ie', 'others');
                   
                } 

                console.log('end', new Date().toLocaleDateString("en-US") + ' ' + new Date().toLocaleTimeString("en-US"));
            }).catch((error) => console.log(error));

Microsoft Edge - SSRS URL does not refresh result render as PDF from Asp.net response.redirect

The problem started when I upgraded my operating system to Windows 10. It comes with Microsoft Edge. My Application was working perfect before. It was returning fresh result from SSRS as PDF. I was using following URL in response.redirect

http://servername/Reportserver?/SSRSRPT2RDL/Main&rs:Command=Render&rs:Format=PDF&year=2018&source=Menu

After upgrade, I have started receiving results from cache. I was wondering what happened suddenly. so I started looking at web page Headers - Status Code. It was 304 (Not Modified). Which means it was not refreshing data and returning results from Cache.

To solve the problem, I have added "rs:ClearSession=true" in the URL. This solved my issue.

http://servername/Reportserver?/SSRSRPT2RDL/Main&rs:Command=Render&rs:Format=PDF&rs:ClearSession=true&year=2018&source=Menu

Thanks

How to make ViewState secure and encrypted in ASP.NET

We can secure and encrypt ViewState by enabling these settings "EnableViewStateMAC" and "ViewStateEncryptionMode" in web.config:

<pages enableViewStateMac="true" ViewStateEncryptionMode="Always"/> 

 

Difference between Stored Procedure and Function in SQL Server

1. Functions must always return a value (either a scalar value or a table). Stored procedures may return a scalar value, a table value or nothing at all.

2. Functions can have only input parameters whereas Stored Procedures can have input/output parameters .

3. Functions can be called from Stored Procedure whereas Stored Procedures cannot be called from Function.

4. Stored Procedure allows SELECT as well as INSERT/UPDATE/DELETE statement whereas Function allows only SELECT statement.

5. Stored Procedures can not be utilized in a SELECT statement whereas Function can be embedded in a SELECT statement.

6. Stored Procedures cannot be used in the SQL statements anywhere in the WHERE/HAVING/SELECT section whereas Function can be.

7. The most important feature of stored procedures over function is to retention and reuse the execution plan while in case of function it will be compiled every time.

8. Functions that return tables can be treated as another rowset. This can be used in JOINs with other tables.

9. Exception can be handled by try-catch block in a Stored Procedure whereas try-catch block cannot be used in a Function.

10. We can go for Transaction Management in Stored Procedure whereas we can't go in Function.

11. Stored procedures are called independently, using the EXEC command, while functions are called from within another SQL statement

A very simple example on System.Reflection in Asp.net

Today I will show you a very simple example on Reflection.

Follows the steps:

Step 1. Create a project with asp.net empty web application and name it "ReflectApp".

Step 2. Create a web form in it and paste following code and run it.

Public Class WebForm1
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, 
                            ByVal e As System.EventArgs) Handles Me.Load
        Dim currentAppName = System.Reflection.Assembly.Load("ReflectApp")

        For Each type As Type In currentAppName.GetTypes
            If type.Name = "Customer" Then
                Dim o As Object = Activator.CreateInstance(type)

                Dim mInfo As System.Reflection.MethodInfo = type.GetMethod("getName")

                If mInfo IsNot Nothing Then
                    Dim result As String = mInfo.Invoke(o, Nothing)

                    Response.Write(result)
                End If

                Exit For
            End If

        Next 
    End Sub
    Public Class Customer
        Private Property _Name As String

        Sub New()
            _Name = "John Miller"
        End Sub

        Public Function getName() As String
            Return _Name
        End Function

    End Class

End Class

Result will be: John Miller

You can debug and see how it works.

CSS or Stylesheets : IIS displaying page differently when localhost is used in URL vs. Hostname or Computername or IP address or Machinename

To solve this issue: just add following line in your <head> tag.

<head>
<meta http-equiv="X-UA-Compatible" content="IE=edge"/>
</head>

Explain with example ISNULL, NULLIF and COALESCE in SQL Server

ISNULL : Replaces NULL with the specified replacement value.

NULLIF : Returns a null value if the two specified expressions are equal.

COALESCE : Returns the first non-null argument.(msdn: Evaluates the arguments in order and returns the current value of the first expression that initially does not evaluate to NULL).

Here are the examples and it's results:

SELECT ISNULL(null,1)
--Result: 1

SELECT NULLIF(1,1)
--Result: NULL

SELECT COALESCE(1,null,null,null)
--Result: 1

SELECT COALESCE(null,2,3,4)
--Result: 2

SELECT COALESCE(null,null,3,4)
--Result: 3

SELECT COALESCE(null,null,null,4)
--Result: 4

SELECT ISNULL(NULLIF(COALESCE(null,null,null,4),4),1)
--Result: 1

A very simple example on KnockoutJS in Asp.net

Today I will show you a very simple example on KnockoutJS in Asp.net

Please follows the steps:

Step 1: Create a project with Asp.net empty web application and add web form.

Step 2: Now, paste following code in "body" tag of your aspx page.

<body>
     
    <p>First name: <strong data-bind="text: firstName"></strong></p>
    <p>Last name: <strong data-bind="text: lastName"></strong></p>
    <p>
        First name:
            <input data-bind="value: firstName" />
    </p>
    <p>
        Last name:
            <input data-bind="value: lastName" />
    </p>
    <script
        src="http://ajax.aspnetcdn.com/ajax/knockout/knockout-2.1.0.js">
    </script>
    <script>

        function AppViewModel() {
            this.firstName = ko.observable("John");
            this.lastName = ko.observable("Miller");
        }

        // Activates knockout.js
        ko.applyBindings(new AppViewModel());
    </script>
</body>

Now run your web form and try to change first name, it will automatically change the first name in the label as well.

How to bind dynamically HTML Ordered List in Asp.net using AngularJS?

Today I will show you a very simple example on binding HTML Ordered List dynamically in Asp.net using AngularJS.

Follows the steps:

Step 1: Create a project with asp.net empty web application and add web form in it.

Step 2: Now, paste following code in ".aspx" page

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <div ng-app="" ng-controller="itemController">
            <ol>
                <li ng-repeat="item in items">{{ item }}
                </li>
            </ol>
        </div>

        <script>
            function itemController($scope) {
                $scope.items = [<%=items%>];
            }

        </script>
        <script 
            src="//ajax.googleapis.com/ajax/libs/angularjs/1.2.15/angular.min.js">

        </script>

    </form>
</body>
</html>

Step 3: Now, paste following code in ".aspx.vb" code behind page

Public Class WebForm1
    Inherits System.Web.UI.Page

    Public items As String = ""

    Protected Sub Page_Load(ByVal sender As Object,
                            ByVal e As System.EventArgs) Handles Me.Load

        If Not Page.IsPostBack Then
            'You can change this items dynamically '
            items = "'Orange', 'Apple', 'Banana', 'Grape', 'Watermelon'"
        End If

    End Sub

End Class

Result will be:

1.Orange
2.Apple
3.Banana
4.Grape
5.Watermelon

How to check or compare that two dates, not including time, are equal? in Asp.net

A very simple example of comparing two dates without including time as below:

One Way:

Dim date1 As Date = CDate("8/1/2014 11:00:00 PM")
Dim date2 As Date = CDate("8/1/2014 02:25:15 AM")

Dim result As Boolean = date1.Date.Equals(date2.Date)
'Result: True

Second Way:

Dim date1 As Date = CDate("8/1/2014 11:00:00 PM").ToShortDateString()
Dim date2 As Date = CDate("8/1/2014 02:25:15 AM").ToShortDateString()

Dim result As Boolean = Date.Equals(date1, date2)
'Result: True