js正则表达式校验正数、负数、和小数:^(\-|\+)?\d+(\.\d+)?$
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title></title> <script type="text/javascript"> function validation() { var val = document.getElementById("txtNumber").value; var regu = /^(\-|\+)?\d+(\.\d+)?$/; if (val != "") { if (!regu.test(val)) { document.getElementById("labResult").style.color = "red"; document.getElementById("labResult").innerHTML = "验证失败!"; } else { document.getElementById("labResult").style.color = "green"; document.getElementById("labResult").innerHTML = "验证成功!"; } } } </script> </head> <body> <input id="txtNumber" name="txtNumber" type="text" /> <input id="btnValidation" name="btnValidation" type="button" value="校验" onclick="validation()" /> 验证结果:<label id="labResult" ></label> </body> </html>