在textarea输入Tab

2006-08-23 00:00:00 作者：

在textarea输入Tab

var code, sel, tmp, r 
    var tabs="" 
    event.returnValue = false 
    sel =event.srcElement.document.selection.createRange() 
    r = event.srcElement.createTextRange()

switch (event.keyCode) 
    { 
        case (8)    : 
            if (!(sel.getClientRects().length > 1)) 
            { 
                event.returnValue = true 
                return 
            } 
            code = sel.text 
            tmp = sel.duplicate() 
            tmp.moveToPoint(r.getBoundingClientRect().left, sel.getClientRects()[0].top) 
            sel.setEndPoint("startToStart", tmp) 
            sel.text = sel.text.replace(/^\t/gm, "") 
            code = code.replace(/^\t/gm, "").replace(/\r\n/g, "\r") 
            r.findText(code) 
            r.select() 
            break 
        case (9)    : 
            if (sel.getClientRects().length > 1) 
            { 
                code = sel.text 
                tmp = sel.duplicate() 
                tmp.moveToPoint(r.getBoundingClientRect().left, sel.getClientRects()[0].top) 
                sel.setEndPoint("startToStart", tmp) 
                sel.text = "\t"+sel.text.replace(/\r\n/g, "\r\t") 
                code = code.replace(/\r\n/g, "\r\t") 
                r.findText(code) 
                r.select() 
            } 
            else 
            { 
                sel.text = "\t" 
                sel.select() 
            } 
            break 
        case (13)    : 
            tmp = sel.duplicate() 
            tmp.moveToPoint(r.getBoundingClientRect().left, sel.getClientRects()[0].top) 
            tmp.setEndPoint("endToEnd", sel)

for (var i=0; tmp.text.match(/^[\t]+/g) && i<tmp.text.match(/^[\t]+/g)[0].length; i++)    tabs += "\t" 
            sel.text = "\r\n"+tabs 
            sel.select() 
            break 
        default        : 
            event.returnValue = true 
            break 
    } 
} 
</script> 
<textarea rows="24" onkeydown="editTab()" style="width:100%" name="filetext" cols="80"></textarea>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]