国产探花免费观看_亚洲丰满少妇自慰呻吟_97日韩有码在线_资源在线日韩欧美_一区二区精品毛片,辰东完美世界有声小说,欢乐颂第一季,yy玄幻小说排行榜完本

首頁 > 編程 > JavaScript > 正文

JavaScript讓Textare、a支持tab按鍵的方法

2019-11-02 14:16:53
字體:
來源:轉載
供稿:網友

   本文實例講述了JavaScript讓Textarea支持tab按鍵的方法。分享給大家供大家參考。具體實現方法如下:

  ?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 HTMLTextAreaElement.prototype.getCaretPosition = function () { //return the caret position of the textarea return this.selectionStart; }; HTMLTextAreaElement.prototype.setCaretPosition = function (position) { //change the caret position of the textarea this.selectionStart = position; this.selectionEnd = position; this.focus(); }; HTMLTextAreaElement.prototype.hasSelection = function () { //if the textarea has selection then return true if (this.selectionStart == this.selectionEnd) { return false; } else { return true; } }; HTMLTextA
歐美電影[www.aikan.tv/xzhtml/10/]
reaElement.prototype.getSelectedText = function () { //return the selection text return this.value.substring(this.selectionStart, this.selectionEnd); }; HTMLTextAreaElement.prototype.setSelection = function (start, end) { //change the selection area of the textarea this.selectionStart = start; this.selectionEnd = end; this.focus(); }; var textarea = document.getElementsByTagName('textarea')[0]; textarea.onkeydown = function(event) { //support tab on textarea if (event.keyCode == 9) { //tab was pressed var newCaretPosition; newCaretPosition = textarea.getCaretPosition() + " ".length; textarea.value = textarea.value.substring(0, textarea.getCaretPosition()) + " " + textarea.value.substring(textarea.getCaretPosition(), textarea.value.length); textarea.setCaretPosition(newCaretPosition); return false; } if(event.keyCode == 8){ //backspace if (textarea.value.substring(textarea.getCaretPosition() - 4, textarea.getCaretPosition()) == " ") { //it's a tab space var newCaretPosition; newCaretPosition = textarea.getCaretPosition() - 3; textarea.value = textarea.value.substring(0, textarea.getCaretPosition() - 3) + textarea.value.substring(textarea.getCaretPosition(), textarea.value.length); textarea.setCaretPosition(newCaretPosition); } } if(event.keyCode == 37){ //left arrow var newCaretPosition; if (textarea.value.substring(textarea.getCaretPosition() - 4, textarea.getCaretPosition()) == " ") { //it's a tab space newCaretPosition = textarea.getCaretPosition() - 3; textarea.setCaretPosition(newCaretPosition); } } if(event.keyCode == 39){ //right arrow var newCaretPosition; if (textarea.value.substring(textarea.getCaretPosition() + 4, textarea.getCaretPosition()) == " ") { //it's a tab space newCaretPosition = textarea.getCaretPosition() + 3; textarea.setCaretPosition(newCaretPosition); } } }
發表評論 共有條評論
用戶名: 密碼:
驗證碼: 匿名發表
主站蜘蛛池模板: 平湖市| 新民市| 舟曲县| 修文县| 陇川县| 富裕县| 梓潼县| 图木舒克市| 海晏县| 普兰县| 锡林浩特市| 保山市| 安阳市| 公安县| 唐河县| 龙井市| 水富县| 景东| 扶绥县| 射洪县| 闽侯县| 通辽市| 剑河县| 玉田县| 新丰县| 天祝| 凤阳县| 灌阳县| 同德县| 红原县| 哈巴河县| 北川| 班玛县| 平邑县| 汪清县| 新宁县| 达日县| 和静县| 海淀区| 永春县| 微博|