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How to use the concat() function of the String class in Java to concatenate two strings
How to use the concat() function of the String class in Java to concatenate two strings
Jul 26, 2023 pm 02:03 PM
How to use the concat() function of the String class in Java to splice two strings
In Java, the String class is a very commonly used class that provides many methods for manipulating strings. One of the most commonly used methods is the concat() function, which can be used to concatenate two strings.
The prototype of the concat() function is as follows:
public String concat(String str)
This function accepts a parameter str, concatenates it to the string that calls the method, and returns the concatenated result.
The following is a sample code that shows how to use the concat() function to splice two strings:
public class StringConcatExample {
public static void main(String[] args) {
String str1 = "Hello";
String str2 = "World";
// 使用concat()函數(shù)拼接兩個字符串
String result = str1.concat(str2);
System.out.println(result); // 輸出 "HelloWorld"
}
}In the above code, we first define two strings str1 and str2 , which are "Hello" and "World" respectively. We want to concatenate these two strings to get "HelloWorld".
When using the concat() function, we will call it with the string as the caller and pass it another string as the parameter. In the above example, we called the concat() function of str1 and passed str2 as a parameter to it. The concat() function concatenates two strings and returns the concatenated result.
Finally, we use the System.out.println() function to print out the result, and the output result is "HelloWorld".
In addition to using the concat() function, we can also use the " " operator to concatenate strings. For example, we can use the following code to achieve the same function:
public class StringConcatExample {
public static void main(String[] args) {
String str1 = "Hello";
String str2 = "World";
// 使用"+"操作符拼接兩個字符串
String result = str1 + str2;
System.out.println(result); // 輸出 "HelloWorld"
}
}The above code has the same function as the previous code, but uses the " " operator to concatenate strings. In this case, Java will automatically use the concat() function of the String class to concatenate strings.
To summarize, the String class in Java provides many convenient methods to operate strings. The concat() function is a common method used to concatenate two strings. We can use this function to concatenate two strings to get a new string. In addition, we can also use the " " operator to concatenate strings. Whether you use the concat() function or the " " operator, you can achieve the same purpose. In actual programming, we can choose to use the appropriate method according to our needs.
The above is the detailed content of How to use the concat() function of the String class in Java to concatenate two strings. For more information, please follow other related articles on the PHP Chinese website!
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