


Detailed explanation of the differences in usage of html(), text(), and val() attributes in jquery
html(), text(), val() introduction
1.HTML
html(): Get the html content of the first matching element. This function cannot be used with XML documents. But it can be used for XHTML documents
html(val): Set the html content of each matching element. This function cannot be used with XML documents. But it can be used for XHTML documents.
2.TEXT
text(): Get the content of all matching elements.
The result is the text combined from the text content contained in all matching elements. This method works for both HTML and XML documents.
text(val): Set the text content of all matching elements
Similar to html(), but will encode HTML (replace "" with the corresponding HTML entities).
3.VAL
val(): Get the current value of the first matching element.
val(val): Set the value of each matching element.
The difference between html(), text() and val()
First of all, there are two methods in html attribute, one has parameters, A no-parameter
1. No-parameter html(): Get the html content of the first matching element. This function cannot be used with XML documents. But it can be used for XHTML documents, returning a String
Example:
html page code:
Hello
jquery code: $( "div").html();
Result: Hello
2. Parameter html (val): Set the html content of each matching element. This function cannot be used with XML documents. But it can be used for XHTML documents. Return a jquery object
html page code:
jquery code: $("div").html("
Nice to meet you
") ;Result: [
Nice to meet you
Secondly, there are two methods in the text attribute, one with parameters and one with No parameters
1. No parameters text(): Get the content of all matching elements. The result is the text combined from the text content contained in all matching elements. What is returned is a String
Example:
html page code:
Hello fine
Thank you!
jquery code: $("p").text();
Result: HellofineThankyou!
2. Parameter text (val): Set the text content of all matching elements, and html( ) is similar, but will encode HTML (replace "" with the corresponding HTML entities). Return a jquery object
html page code:
Test Paragraph.
jquery code: $("p").text("Some new text.");
Result:[
Some new text.
]Finally, there are two methods in the val() attribute, one with parameters and one without parameters.
1. Parameterless val(): Get the current value of the first matching element. In jQuery 1.2, you can return the value of any element. Including select. If multiple selections are made, an array containing the selected values will be returned.
Returns a String, array
Instance
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <script src="js/jquery.js" type="text/javascript"></script> <!-- <script src="http://code.jquery.com/jquery-latest.js"></script> --> <title> 获取或设置元素的内容</title> <style type="text/css"> body{font-size:15px;text-align:center} div{border:solid 0px #666;padding:5px;width:220px;margin:5px} </style> <script type="text/javascript"> $(function() { var strHTML = $("#divShow").html();// 获取HTML 内容(包含div下面的两个格式) var strHTML2 = $("#divShow b i").html(); //获取HTML内容 var strHTML3 = $("div").html(); var strText = $("#divShow").text();// 获取文本内容 var strText2 = $("div").text(); $("#divHTML").html(strHTML);// 设置HTML 内容 $("#divHTML2").html(strHTML2); //设置HTML内容 $("#divHTML3").html(strHTML3); //设置HTML内容 $("p").html(strHTML); $("#divText").text(strText);// 设置文本内容 $("#divText2").text(strText2);// 设置文本内容 $("a").text(strText); $("select").change(function() { // 设置列表框change 事件 // 获取列表框所选中的全部选项的值 alert($("select").val()); var strSel = $("select").val().join(","); $("input").val(strSel); // 显示列表框所选中的全部选项的值 }) }) </script> </head> <body> <table border="1" bordercolor="#A9A9A9" cellspacing="0"> <tr><td>******************************</td><td>*******************************************</td></tr> <tr> <td><div id="divShow"><b><i>Write Less Do More</i></b></div></td> <td>这是原内容</td> </tr> <tr> <td><div id="divShow"><b><i>Write XXXX Do XXXX</i></b></div></td> <td>这是原内容</td> </tr> <tr><td>******************************</td><td>*******************************************</td></tr> <tr> <td><div id="divHTML">1</div></td> <td>获取原内容(连带内容的格式)后以html方式输出</td> </tr> <tr> <td><div id="divHTML2">2</div></td> <td>获取原内容(不带内容的格式)后以html方式输出</td> </tr> <tr> <td><div id="divHTML3">3</div></td> <td>获取原内容(获取第一个匹配元素的内容)后以html方式输出</td> </tr> <tr> <td><p></p></td> <td>HTML方式设置段落的文本</td> </tr> <tr> <td><p></p></td> <td>如果这个也有内容了,就是设置每个匹配元素的内容</td> </tr> <tr><td>******************************</td><td>*******************************************</td></tr> <tr> <td><div id="divText">4</div></td> <td>获取原内容后以text方式输出</td> </tr> <tr> <td><div id="divText2"></div></td> <td>获取原内容(获取所有匹配元素的内容)后以text方式输出</td> </tr> <tr> <td><a></a></td> <td>TEXT方式设置段落的文本</td> </tr> <tr> <td><a></a></td> <td>如果这个也有内容了,就是设置每个匹配元素的内容</td> </tr> <tr><td>******************************</td><td>*******************************************</td></tr> <tr> <td> <select multiple="multiple"style="height:96px;width:85px"> <option value="1">Item 1</option> <option value="2">Item 2</option> <option value="3">Item 3</option> <option value="4">Item 4</option> <option value="5">Item 5</option> <option value="6">Item 6</option> </select> <select> <option value="7">Item 7</option> <option value="8">Item 8</option> <option value="9" selected>Item 9</option> </select> </td> <td> </td> </tr> <tr> <td><input ></input></td> <td><input ></input></td> </tr> </table> </body> </html>
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