js处理数字保留2位小数，强制保留2位小数不够补上.00

http://blog.csdn.net/kongjiea/article/details/42643091 1、保留两位小数 //功能：将浮点数四舍五入，取小数点后2位2、//制保留2位小数，如：2，会在2后面补上00.即2.00 <pre> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Test</title> <script type="text/javascript" src="js/jq.js"></script> </head> <script type="text/javascript"> //保留两位小数 //功能：将浮点数四舍五入，取小数点后2位 function toDecimal(x) { var f = parseFloat(x); if (isNaN(f)) { return; } f = Math.round(x*100)/100; return f; } //制保留2位小数，如：2，会在2后面补上00.即2.00 function toDecimal2(x) { var f = parseFloat(x); if (isNaN(f)) { return false; } var f = Math.round(x*100)/100; var s = f.toString(); var rs = s.indexOf('.'); if (rs < 0) { rs = s.length; s += '.'; } while (s.length <= rs + 2) { s += '0'; } return s; } function fomatFloat(src,pos){ return Math.round(src*Math.pow(10, pos))/Math.pow(10, pos); } document.write("四舍五入 ") document.write("3.14159267保留2位小数：" + toDecimal(3.14159267)+" "); document.write("3.14159267强制保留2位小数：" + toDecimal2(3.14159267)+" "); document.write("3.14159267保留2位小数：" + toDecimal(3.14559267)+" "); document.write("3.14159267强制保留2位小数：" + toDecimal2(3.15159267)+" "); document.write("3.14159267保留2位小数：" + fomatFloat(3.14559267, 2)+" "); document.write("3.14159267保留1位小数：" + fomatFloat(3.15159267, 1)+" "); document.write("五舍六入 ") document.write("1000.003保留2位小数：" + 1000.003.toFixed(2)+" "); document.write("1000.08保留1位小数：" + 1000.08.toFixed(1)+" "); document.write("1000.04保留1位小数：" + 1000.04.toFixed(1)+" "); document.write("1000.05保留1位小数：" + 1000.05.toFixed(1)+" "); document.write("科学计数 ") document.write(3.1415+"科学技术后："+3.1415.toExponential(2)+" "); document.write(3.1455+"科学技术后："+3.1455.toExponential(2)+" "); document.write(3.1445+"科学技术后："+3.1445.toExponential(2)+" "); document.write(3.1465+"科学技术后："+3.1465.toExponential(2)+" "); document.write(3.1665+"科学技术后："+3.1665.toExponential(1)+" "); document.write("精确到n位，不含n位 ") document.write("3.1415精确到小数点第2位" + 3.1415.toPrecision(2)+" "); document.write("3.1455精确到小数点第3位" + 3.1465.toPrecision(3)+" "); document.write("3.1445精确到小数点第2位" + 3.1415.toPrecision(2)+" "); document.write("3.1465精确到小数点第2位" + 3.1455.toPrecision(2)+" "); document.write("3.166592679287精确到小数点第5位" + 3.141592679287.toPrecision(5)+" "); </script> <body> <input type="text" id="Score" /> </body> </html> </pre> js处理数字相关文章：<a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/25731461" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">onkeyup限制输入框只能输入数字</a> <a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/40185951" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">移动端手机网站限制input只能输入数字</a> <a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/42523891" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">toFixed方法重写，toFixed四舍五入在数值很小时的精度问题</a> <a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/42643091" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">js处理数字保留2位小数，强制保留2位小数不够补上.00</a> <a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/41247845" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">数字格式化，格式数字保留2位小数点，格式数字自定义保留n位小数点</a> <a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/42078463" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">js数字金额大写转换</a> 数字格式化相关文章：<a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/41247845" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">数字格式化，格式数字保留2位小数点，格式数字自定义保留n位小数点</a> <a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/25060857" style="color:rgb(0,0,0); text-decoration:none; font-family:'Microsoft YaHei'; font-size:20px; line-height:30px">数字格式化为金额格式（3位一个逗号隔开）如：100,000.00</a> <a name="t0"></a><a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/38089589" style="color:rgb(0,0,0); text-decoration:none">js 填写银行卡号时，每4个数字用空格隔开</a> js限制数字相关文章： <a name="t1"></a><a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/24309121" style="text-decoration:none; color:rgb(0,0,0)">常用正则表达式</a> <a name="t2"></a><a target="_blank" href="http://blog.csdn.net/kongjiea/article/details/39644599" style="text-decoration:none; color:rgb(0,0,0); font-family:'microsoft yahei'; font-size:18px; font-weight:bold">js限制input只能输入有效的数字，有且只有一个小数点，第一个不能为小数点</a>