找到了这个解决方案。不是基于jquery的，但是将其集成到jquery中没有问题：
function doGetCaretPosition (oField) { // Initialize var iCaretPos = 0; // IE Support if (document.selection) { // Set focus on the element oField.focus(); // To get cursor position, get empty selection range var oSel = document.selection.createRange(); // Move selection start to 0 position oSel.moveStart('character', -oField.value.length); // The caret position is selection length iCaretPos = oSel.text.length; } // Firefox support else if (oField.selectionStart || oField.selectionStart == '0') iCaretPos = oField.selectionDirection=='backward' ? oField.selectionStart : oField.selectionEnd; // Return results return iCaretPos;}
