java Java 中的 NumberFormat 解析()方法，示例

Java 中的 NumberFormat 解析()方法，示例

原文:https://www . geesforgeks . org/number format-parse-method-in-Java-with-examples/

The parse(str) method is a built-in method of the java.text.NumberFormat which parses text from the beginning of the given string to produce a number. The method may not use the entire text of the given string

语法:

java public Number parse?(String str)

参数:函数接受一个字符串字符串，其开头应该被解析。

返回值:该函数返回一个从字符串中解析出来的数字。

异常:如果指定字符串的开头无法解析，函数会抛出解析异常。

下面是上述功能的实现:

程序 1 :

```java // Java program to implement // the above function

import java.text.NumberFormat; import java.util.Locale; import java.text.ParsePosition;

public class Main {     public static void main(String[] args)         throws Exception     {

// Get the number instance         NumberFormat nF             = NumberFormat.getNumberInstance();

// Prints the parsed number or NULL         System.out.println("Number parsed: "                            + nF.parse("567"));     } } ```

Output:

```java Number parsed: 567

```
The parse(str, parseIndex) method is a built-in method of the java.text.NumberFormat which parses a number from the text and returns a Long if possible, otherwise a Double. If IntegerOnly is set, will stop at a decimal point (or equivalent; e.g., for rational numbers “1 2/3”, will stop after the 1).

语法:

公共抽象数字解析(字符串，解析位置解析索引)

参数:该功能接受两个参数，描述如下:
- str: specifies the string to be parsed.
  
  解析索引:指定解析位置
返回值:该函数返回一个从字符串中解析出来的数字。

下面是上述功能的实现:

程序 1 :

```java // Java program to implement // the above function

import java.text.NumberFormat; import java.util.Locale; import java.text.ParsePosition;

public class Main {     public static void main(String[] args)         throws Exception     {

// Get the number instance         NumberFormat nF             = NumberFormat.getNumberInstance();

// Prints the parsed number or NULL         System.out.println("Number parsed: "                            + nF.parse("567",                                       new ParsePosition(1)));     } } ```

Output:

```java Number parsed: 67

```