js daily summary

How 1.html introduction of css and js files

css: <link rel = "stylesheet" href = "css / index1.css (this is the address of my file)">

script: <script type = "text / javascript" src = "js / jquery-3.4.1.min.js (this is the address of my folder)"> </ script>

2.jquery common operations

Setting and returns HTML () method of the selected content element (inner HTML).

js

<script>
  $(document).ready(function(){
            $("#btn1").click(function(){
                $("p").html("Hello world");
            });
        });
</script>

findindex and tostring used in combination to find in the current item is an array of items:

 table_list = [1,1,2,35,5,9]

        $(document).ready(function(){
            itemNum = table_list.findIndex(function(item){
                return item.toString() = myItem.toString()
            });
        });

Val () method returns the set value or the selected element

 $(document).ready(function(){
            $("#btn1").click(function(){
                $(":text").val("hello world");
            });
        });

Get value exists inside the select data items selected

<select  class="mySelect">
     <option value="switch" data-name="开关">开关</option>
     <option value="light" data-name="灯光">灯光</option>
</select>

$ ( "mySelect.") find ( "option: selected") attr ( "data-name"); data- obtaining the selected item.. name value of "switch"; $ 
( ".mySelect") Val (). ; get the value of the switch value.

parselnt XX is converted to the number: Number () for all types, parseInt () and parseFloat () applied to the string

Analyzing myitem indexOf itemArray exists in the array, there is a return to the first index, -1 otherwise:

indexOf () method is to look for the positive sequence, lastIndexOf () is a flashback to find // https://www.cnblogs.com/clear93/p/7928218.html

var index = JSON.stringify(itemArray).indexOf(JSON.stringify(myitem));

append html and values ​​inserted into the document required

 $("#btn").click(function(){
            html = '<tr>'
                + '<td>' + '<img src="./images/item.png" alt="">' + '</td>' 
                + '<td>' + '<span>品牌： </span>'  + '<span>' + $(".myValue").val() + '</span>' + '</td>'
                + '</tr>';
                $("list").append(html);

        });

location.reload () to refresh the page

        window.location.reload

 

attr () and removeAttr ()

$ ( "input.") attr ( "placeholder", " Please enter your password"). 
        $ ( "the INPUT") removeAttr ( "DATE-targer").;

prop() 和 removeprop()

<script>  
</scrip$("#btn").prop("checked");  //truet>
<label>
<input type="checkbox" value="复选框" id="btn" checked = "true" disabled = "">
</label>

Depth understanding

<script>
    $(document).ready(function(){
                $("btn").click(function(){
                    $("p").removeAttr("style");
                });
            });
</script>