一. 获取光标位置：
获取光标位置
function getCursortPosition (textDom) {
var cursorPos = 0;
if (document.selection) {
// IE Support
textDom.focus ();
var selectRange = document.selection.createRange();
selectRange.moveStart ('character',-textDom.value.length);
cursorPos = selectRange.text.length;
}else if (textDom.selectionStart || textDom.selectionStart == '0') {
// Firefox support
cursorPos = textDom.selectionStart;
}
return cursorPos;
}
二. 设置光标位置：
三. 获取选中文字：
获取选中文字
function getSelectText() {
var userSelection,text;
if (window.getSelection) {
// Firefox support
userSelection = window.getSelection();
} else if (document.selection) {
// IE Support
userSelection = document.selection.createRange();
}
if (!(text = userSelection.text)) {
text = userSelection;
}
return text;
}
四. 选中特定范围的文本：
textLength){
startPos = textLength;
}
if(endPos > textLength){
endPos = textLength;
}
if(startPos < 0){
startPos = textLength + startPos;
}
if(endPos < 0){
endPos = textLength + endPos;
}
if(textDom.createTextRange){
// IE Support
var range = textDom.createTextRange();
range.moveStart("character",-textLength);
range.moveEnd("character",-textLength);
range.moveStart("character",startPos);
range.moveEnd("character",endPos);
range.select();
}else{
// Firefox support
textDom.setSelectionRange(startPos,endPos);
textDom.focus();
}
}
}
