Javascript tips

Below are some of the tips in javascript and html.

html select
<select>
<option value="" selected disabled hidden>Choose here</option>
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
<option value="4">Four</option>
<option value="5">Five</option>
</select>

String functions
key = chart_id.split("_");
chart_name = key[1];
if(char_name.includes("val_"))
{
}

For loop - alternate elements (even and odd)
for(var i=0; i< arr.length; i++)
{
if(i%2 == 0)
{
}
else if(i%2 != 0)
{
}
else
{
}
}
Slice function
coars.slice(0,val_count); // not inclusive of the end


div updates and removal
$('#myCharr').update()
$('#myCharr').remove();

lambda function
keys = key.map((x) => x);

Handling Data tables and wildcard query selector
$(document).ready(function() {
$('#example').dataTable();
} );
$("table[id^='Table_']")

Object.keys iterating through dictionary keys and values
for (var i = 0; i < Object.keys(params).length; i++) {
count_params[Object.keys(params)[i]] = 0;
}

Query selector for event listener and accessing value

$('button[id^="charts_"]').on('click', function (event) {
});
document.getElementById('dataframess').value;

Sort the array with the index to find out the sorted order
function sort_with_index(test)
{
var test_with_index = [];
for (var i in test) {
var y = test[i];
if(y=="")
{
y="100";
}
else
{
y= String(y);
y = y.substring(0, y.length - 1);;
}
////alert("y"+y);
test_with_index.push([parseInt(y), i]);
}

dynamic url href and clicking on it
var a = document.createElement('a');
a.download = 'roles_org.png';
a.href = base64_url;
a.click();

highlighting the text in a table
$("#display_table").mousedown(function (event) {
mouseXPosition = event.pageX; //register the mouse down position
});
$("#display_table").mouseup(function (event)
{
target = event.target.id;
var highlighted = false;
var selection = window.getSelection();
var selectedText = selection.toString(); alert("selectedText"+selectedText);
}

mark for highlighting

<mark style='color: white; background-color: "+colored+";'>" + selectedTexts + "</mark>