js控制input控件只能输入数字

废话不多说，直接上代码

//js控制input控件只能输入数字    
        function OnlyinputNumber(e, obj, withFraction) {
            if (!e) {
                e = window.event;
            }
            if (e.which) {
                key = e.which;
            } else {
                key = e.keyCode;
            }
            validNumber = false;
            if (key == 8 //Backspace
                || key == 46 //Delete
                || key >= 35 && key <= 37 //End, Home, Left
                || key == 39 //Right
                || key == 189 //负号“-”
                ) {
                validNumber = true;
            }
            if (!e.shiftKey) {
                //only check shift is not pressed
                if (withFraction
                    && obj.value.length > 0
                    && key == 190 //period
                    && obj.value.indexOf(".") == -1) {
                    validNumber = true;
                }
                if (key == 48 && obj.value.length > 0) { // 0
                    validNumber = true;
                }
                if (key >= 49 && key <= 57) { // 1~9
                    validNumber = true;
                }
            }
            if (!validNumber) {
                if (e.preventDefault) {
                    e.preventDefault();
                } else {
                    e.returnValue = false;
                }
            }
        }