// 判斷一個字符串是否都為數字
public boolean isDigit(String strNum) {
return strNum.matches("[0-9]{1,}");
}
// 判斷一個字符串是否都為數字
public boolean isDigit(String strNum) {
Pattern pattern =
Pattern.compile("[0-9]{1,}");
Matcher matcher = pattern.matcher((CharSequence) strNum);
return matcher.matches();
}
//截取數字
public String getNumbers(String content) {
Pattern pattern =
Pattern.compile("\\d+");
Matcher matcher = pattern.matcher(content);
while (matcher.find()) {
return matcher.group(0);
}
return "";
}
// 截取非數字
public String splitNotNumber(String content) {
Pattern pattern =
Pattern.compile("\\D+");
Matcher matcher = pattern.matcher(content);
while (matcher.find()) {
return matcher.group(0);
}
return "";
}
// 判斷一個字符串是否含有數字
public boolean HasDigit(String content) {
boolean flag = false;
Pattern p =
Pattern.compile(".*\\d+.*");
Matcher m = p.matcher(content);
if (m.matches()) {
flag = true;
}
return flag;
}
java中判斷字符串是否為數字的四種方法 ：
1.用JAVA自帶的函數
public static boolean isNumeric(String str) {
for (int i = str.length(); --i >= 0;) {
if (!Character.isDigit(str.charAt(i))) {
return false;
}
}
return true;
}
2.可以使用lang3下的包下StringUtils類的方法isNumeric()
String str="1235456";
boolean flag =StringUtils.isNumeric(str);
3..用正則表達式
public static boolean isNumeric(String str) {
Pattern pattern =
Pattern.compile("[0-9]*");
return pattern.matcher(str).matches();
}
4.用ASCII碼
public static boolean isNumeric(String str) {
for (int i = str.length(); --i >= 0;) {
int chr = str.charAt(i);
if (chr < 48 || chr > 57)
return false;
}
return true;
}