如何在Internet Explorer 7中使用jQuery在textarea中获取所选文本？

Question

我尝试了jquery-fieldselection插件来获取textarea中的选定文本.

它在Firefox和Chrome中运行良好,但在Internet Explorer 7中运行不正常.

我使用这样的getSelection()方法:

textarea.getSelection();

当textarea中的12345文本被选中并且所有这些文本被选中时,Firefox和Chrome将返回:

start: 0    // Correct!
end: 5

Internet Explorer 7返回时:

start: 5    // Why ??
end: 5

我正在寻找使用jQuery的跨浏览器解决方案.

Answer 1

只是看了一下tthelibrary,它的行为与IE不同,因为它不支持现代浏览器所做的一些方法..可能是代码不完美..

使用以下方法:

function getInputSelection(el) {
    var start = 0, end = 0, normalizedValue, range,
        textInputRange, len, endRange;

    if (typeof el.selectionStart == "number" && typeof el.selectionEnd == "number") {
        start = el.selectionStart;
        end = el.selectionEnd;
    } else {
        range = document.selection.createRange();

        if (range && range.parentElement() == el) {
            len = el.value.length;
            normalizedValue = el.value.replace(/\r\n/g, "\n");

            // Create a working TextRange that lives only in the input
            textInputRange = el.createTextRange();
            textInputRange.moveToBookmark(range.getBookmark());

            // Check if the start and end of the selection are at the very end
            // of the input, since moveStart/moveEnd doesn't return what we want
            // in those cases
            endRange = el.createTextRange();
            endRange.collapse(false);

            if (textInputRange.compareEndPoints("StartToEnd", endRange) > -1) {
                start = end = len;
            } else {
                start = -textInputRange.moveStart("character", -len);
                start += normalizedValue.slice(0, start).split("\n").length - 1;

                if (textInputRange.compareEndPoints("EndToEnd", endRange) > -1) {
                    end = len;
                } else {
                    end = -textInputRange.moveEnd("character", -len);
                    end += normalizedValue.slice(0, end).split("\n").length - 1;
                }
            }
        }
    }

    return {
        start: start,
        end: end
    };
}

如何使用它:

你需要textarea的dom对象..因此:

var textArea=    $("textarea")[0] or getElementbyId("textareaid");

var selectedText=getInputSelection(textArea);

var start=selectedText.start;
var end=selectedText.end;

现场演示