处理字符串中的换行，将textarea中的带有换行的字符串变为逗号分隔的写法

_setMultipleInputValues: function (param) {
            //Maybe need to modify here for the new parameter 
            //add a method to set input values from textarea
            if (param.Name == "AddedParameter1") {
                bindingElement = true;
                var textareaValue = "";
                textareaValue = $("#" + param.Name + "_textarea").val();
                var c;
                for (var i = 0; i < textareaValue.length; i++)
                {
                    c = textareaValue.substr(i, 1);
                    if (c == "
")
                    {
                        textareaValue = textareaValue.replace("
", ",");
                    }
                }
                $("#" + param.Name + "_fore").val(textareaValue.substr(0, textareaValue.length - 1));
            }
            else {
                var showValue = "";
                var hiddenValue = "";
                $("." + param.Name + "_DropDown_CB").each(function () {
                    if (this.checked && this.value !== "Select All") {
                        showValue += $("[name='" + param.Name + "_DropDown_" + this.value + "_lable']").html() + ",";
                        hiddenValue += this.value + ",";
                    }
                });
                $("#" + param.Name + "_fore").val(showValue.substr(0, showValue.length - 1));
                $("#" + param.Name + "_hidden").val(hiddenValue.substr(0, hiddenValue.length - 1));
            }
        },

直接上代码，下面截图做说明：