Encode - decode base64

https://scotch.io/tutorials/how-to-encode-and-decode-strings-with-base64-in-javascript

Remove Duplicate Values in SharePoint List

<!--Copy all source code, paste it inside Content Editor /  Script Editor-->

<div><h1>Remove Duplicate Values</h1></div>
<div>Enter Your List Name : <input type='text' id='txtList' /></div>
<div>Enter Your Unique Column : <input type='text' id='txtUniColumn' /><input type='button' value='Remove Duplicate Value' onclick='getListItems()'/></div>

<div id='divDel'>Deleted Items
<div id='divDelItems'></div>
</div>

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script type='text/javascript'>

$(document).ready(function(){
debugger;
$('#divDelItems').html('');
$('#divDel').hide();
});

function RemoveDuplicateItems(items, propertyName) {
    var result = [];
     var ExistingItem = [];
    if (items.length > 0) {
        $.each(items, function (index, item) {
            if ($.inArray(item[propertyName], result ) == -1) {
                    if(!IsNullOrUndefined(item[propertyName])){
                             result.push(item[propertyName]);
                    }
            }
            else{
                   if(!IsNullOrUndefined(item[propertyName])){
                            ExistingItem.push(item['Id']+ ' : ' + item[$('#txtUniColumn').val()] );
                   }
           }
        });
    }
    return ExistingItem;
}



function getListItems() {
    $.ajax({
        url:  _spPageContextInfo.siteAbsoluteUrl + "/_api/web/lists/getbytitle('"+$('#txtList').val()+"')/items?$select="+$('#txtUniColumn').val()+",Id&$top=5000&$orderby= Modified desc" ,
        method: "GET",
        headers: { "Accept": "application/json; odata=verbose" },
        success: function(data) {

            var items = data.d.results;
             items = RemoveDuplicateItems(items, $('#txtUniColumn').val());
             $('#divDel').show();
             if(items!=undefined && items.length>0){
             for(var i=0; i<items.length; i++){
                   deleteItems(items[i]);
            }}
        },
        error: function(data) {
            alert(data.responseText);
        }
    });
}
var count = 0;
function deleteItems(Id){
  $.ajax({ 
            url: _spPageContextInfo.webAbsoluteUrl + "/_api/web/lists/getbytitle('"+$('#txtList').val()+"')/items(" + Id.split(':')[0] + ")", 
            type: "POST", 
            contentType: "application/json;odata=verbose", 
            headers: { 
                "Accept": "application/json;odata=verbose", 
                "X-RequestDigest": $("#__REQUESTDIGEST").val(), 
                "IF-MATCH": "*", 
                "X-HTTP-Method": "DELETE", 
            }, 
            success: function(data) { 
                   var cnt = count++;
                  console.log(Id + ' Count - ' );
                  $('#divDelItems').append('<div>' + Id + ' Count - ' + cnt  + '</div>');
            }, 
            error: function(data) { 
                 
            } 
        });
}

</script>

Sharepoint WSP Solution BackUp and Deployment

//For WSP Backup
$farm = Get-SpFarm 
$file = $farm.Solutions.Item("WSP_Solution.wsp").SolutionFile 
$file.SaveAs("E:\FolderName\WSP_Solution.wsp")


//Before add WSP solution, Retract solution from central admin Farm solution and remove Solution from there.
Add-SPSolution "E:\FolderName\WSP_Solution.wsp"
Install-SPSolution –Identity WSP_Solution.wsp –WebApplication "Web App url" –GACDeployment

Disable Future Dates of Calendar from SharePoint Default Forms

//Add this script inside forms or page's script editor

<script src="//code.jquery.com/jquery-3.2.1.min.js" type="text/javascript"></script>
<script type="text/javascript">
var getSPDayDiff = function(date) {
return Math.round(Math.abs(( new Date(1601,0,1).getTime() - date.getTime())/( 24*60*60*1000 ) ) );
}
$(function () {
debugger;
var currentDate = new Date();
//currentDate.setMonth(currentDate.getMonth() + 1);
var minDay = getSPDayDiff(new Date());
var maxDay = getSPDayDiff(currentDate);

var datePicker=$("img[alt='Select a date from the calendar.']").parent();
var onclickStr=datePicker.attr("onclick");
//onclickStr=onclickStr.replace("minjday=109207", "minjday="+minDay);

        onclickStr=onclickStr.replace("minjday=109207", "minjday=109207");

onclickStr=onclickStr.replace("maxjday=2666269", "maxjday="+maxDay);
datePicker.attr("onclick",onclickStr);
});
</script>

Spfx Angular 2

https://www.fmtconsultants.com/sharepoint-framework-spfx-angular2/

https://www.barbarianmeetscoding.com/blog/2016/03/25/getting-started-with-angular-2-step-by-step-1-your-first-component/

https://docs.microsoft.com/en-us/sharepoint/dev/spfx/web-parts/get-started/build-a-hello-world-web-part

rest Batch Operations

https://social.technet.microsoft.com/wiki/contents/articles/30044.sharepoint-online-performing-batch-operations-using-rest-api.aspx

https://www.c-sharpcorner.com/UploadFile/780289/save-mutiple-records-to-sharepoint-2013-using-rest-api-in-a/

Create Host Name Site Collection Using Powershell Script

[string] $ContentDB =  $(Read-Host -prompt "Content Database Name")
[string] $DatabaseServer =  $(Read-Host -prompt "Database Server Name")
[string] $WebApplication =  $(Read-Host -prompt "Web Application Name")
[string] $siteUrl = $(Read-Host -prompt "Site Url")
[string] $SiteName = $(Read-Host -prompt "Site Name")
[string] $SiteOwnerID = $(Read-Host -prompt "Site Owner ID")


New-SPContentDatabase $ContentDB -DatabaseServer $DatabaseServer -WebApplication $WebApplication
New-SPSite $siteUrl -HostHeaderWebApplication $WebApplication -Name $SiteName -OwnerAlias $SiteOwnerID -language 1033 -Template 'STS#0' -ContentDatabase $ContentDB