JS获取和设置光标的位置
<html><head><script language="javascript">function getCursortPosition (ctrl) {//获取光标位置函数var CaretPos = 0;// IE Supportif (document.selection) {ctrl.focus ();var Sel = document.selection.createRange ();Sel.moveStart ('character', -ctrl.value.length);CaretPos = Sel.text.length;}// Firefox supportelse if (ctrl.selectionStart || ctrl.selectionStart == '0')CaretPos = ctrl.selectionStart;return (CaretPos);}function setCaretPosition(ctrl, pos){//设置光标位置函数if(ctrl.setSelectionRange){ctrl.focus();ctrl.setSelectionRange(pos,pos);}else if (ctrl.createTextRange) {var range = ctrl.createTextRange();range.collapse(true);range.moveEnd('character', pos);range.moveStart('character', pos);range.select();}}function A(){alert(getCursortPosition(document.getElementById("a")));}function B(){ setCaretPosition(document.getElementById("a"),5);}</script></head><body><input id="a" type=text name=text1 value="" ><button onclick="A();">获取</bottun> <button onclick="B();">设置</bottun></body></html>onkeyup ="LowerToUpper(this,event.keyCode);"
//小写转大写function LowerToUpper(element,keyCode){ if ((keyCode > 40 || keyCode < 35) && keyCode != 8) { var pos = getCursortPosition(element); element.value = element.value.toUpperCase(); setCaretPosition(element, pos); }}