The Complete Guide to Formatting Placeholders in Golang
Complete Guide to Formatting Placeholders in Golang
In Golang programming, formatting placeholders are a very important part, they allow you to define the style of output and structure, making the output easier to read and understand. This article will introduce formatted placeholders in Golang in detail, including common placeholder types and usage, as well as specific code examples.
1. Common formatting placeholders
In Golang, the common formatting placeholders are as follows:
- %v: Default format. When printing a structure, print the value of each field.
- % v: Similar to %v, but when printing the structure, the names of the structure fields will be included.
- %#v: Print the value represented by Go syntax, that is, the Go syntax representation of the value will be printed.
- %T: The type of printed value.
- %t: Print Boolean value.
- %d: Print integer value.
- %f: Print floating point value.
- %s: Print string.
- %p: Print pointer address.
In addition to the common placeholders mentioned above, Golang also supports more other types of placeholders. You can choose the appropriate placeholder to format the output according to your needs.
2. Code Examples
The following are some specific code examples showing how to use formatted placeholders in Golang:
Example 1: Printing using %v Integers and strings
package main import "fmt" func main() { num := 10 str := "Hello, Golang!" fmt.Printf("num: %v ", num) fmt.Printf("str: %v ", str) }
Run the above code, it will output:
num: 10 str: Hello, Golang!
Example 2: Use %v to print structure fields
package main import "fmt" type Person struct { Name string Age int } func main() { p := Person{"Alice", 25} fmt.Printf("%+v ", p) }
Run the above code, it will output:
{Name:Alice Age:25}
Example 3: Use %d and %f to print integers and floating point numbers
package main import "fmt" func main() { num := 10 pi := 3.14159 fmt.Printf("num: %d ", num) fmt.Printf("pi: %f ", pi) }
Running the above code will output:
num: 10 pi: 3.141590
Through the above examples, you can better Understand the usage and function of formatted placeholders in Golang. Depending on your needs, you can choose appropriate placeholders to format the output to make the code clearer and easier to read.
Conclusion
Formatting placeholders play an important role in Golang programming. It can help you better organize the output content and make the output more precise and clear. I hope that through the introduction of this article, you can better master the use of formatted placeholders in Golang and improve the readability and maintainability of the code.
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