JavaScript gets and sets the cursor position

One. Get cursor Position:

Gets the cursor position 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.select Ionstart;    }    return cursorpos;}

　

Two. Set the cursor position:

Set cursor position function setcaretposition (Textdom, POS) {    if (textdom.setselectionrange) {        //IE        support Textdom.focus ();        Textdom.setselectionrange (POS, POS);    } else if (textdom.createtextrange) {        ///Firefox support        var range = Textdom.createtextrange ();        Range.collapse (true);        Range.moveend (' character ', POS);        Range.movestart (' character ', POS);        Range.Select ();    }}

　　

Three. Get the selected text:

Gets the selected text 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;}

　　

Four. Select a specific range of text:

/*** Select a specific range of text * Parameters: * textdom [JavaScript DOM String] Current Object * startpos [int] Start position * endpos [int] End position */functi        On Setselecttext (Textdom, startpos, endpos) {var startpos = parseint (startpos), Endpos = parseint (Endpos),    TextLength = TextDom.value.length;        if (textLength) {if (!startpos) {startpos = 0;        } if (!endpos) {endpos = TextLength;        } if (Startpos > 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 (); }    }}

　　

Five. Insert text after the cursor:

/*** insert text after cursor * parameter: * textdom [JavaScript DOM String] Current Object * value [Stri    NG] The text to be inserted */function Insertaftertext (textdom, value) {var selectrange;        if (document.selection) {//IE support Textdom.focus ();        Selectrange = Document.selection.createRange ();        Selectrange.text = value;    Textdom.focus (); }else if (Textdom.selectionstart | | textdom.selectionstart = = ' 0 ') {//Firefox support var startpos = TEXTD        Om.selectionstart;        var endpos = textdom.selectionend;        var scrolltop = textdom.scrolltop;        Textdom.value = textDom.value.substring (0, startpos) + value + textDom.value.substring (Endpos, textDom.value.length);        Textdom.focus ();        Textdom.selectionstart = Startpos + value.length;        Textdom.selectionend = Startpos + value.length;    Textdom.scrolltop = scrolltop;        } else {textdom.value + = value;    Textdom.focus (); }}

　　

　

JavaScript gets and sets the cursor position