function getString(str, param){
        var reg = new RegExp("\\" + param + "\\d+\\.\\d+", "g");
        return str.replace(reg, "");
    }

------解决方案--------------------
JScript code
var str = "|12,12.0|13,12.0|14,11.12|";
function testReplace(_str)
{
var reg=new RegExp('\\'+_str+'\\d+\\.\\d+','g'); 
console.log(str.replace(reg,''));
}   
testReplace('|12,');

------解决方案--------------------

var str = "|12,12.0|13,12.0|14,11.12|";
function testReplace(_str)
{
var reg=new RegExp('\\'+_str+'\\d+(\\.\\d+)?','g');  
console.log(str.replace(reg,''));
}  
testReplace('|12,');

------解决方案--------------------

"\\" + param + "\\d+(\\.\\d+)?"
或者干脆
"\\" + param + "[^\|$]+"

------解决方案--------------------

JScript code
    <script type="text/javascript">
        function test(s) {
            var str = "|12,12.0|13,12.0|14,11.12|";
            var reg = new RegExp('\\' + s + '[^|]*', 'g');
            alert(str.replace(reg, ''));
        }
        test('|13,');
    </script>