Go 程序判断字符是否为数字

编写一个 Go 程序来判断字符是否为数字。unicode.IsDigit 检查 Rune 是否为数字。我们使用了 If else 语句（if unicode.IsDigit(r)）以及 unicode IsDigit 函数来判断给定的字符是否为数字。

package main

import (
    "bufio"
    "fmt"
    "os"
    "unicode"
)

func main() {

    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter Any Character to Check Digit = ")
    r, _, _ := reader.ReadRune()

    if unicode.IsDigit(r) {
        fmt.Printf("%c is a Digit\n", r)
    } else {
        fmt.Printf("%c is Not a Digit\n", r)
    }
}

Unicode 包还有一个 IsNumber 函数（if unicode.IsNumber(r)）来检查字符是否为数字。在这里，我们使用了这个函数。

package main

import (
    "bufio"
    "fmt"
    "os"
    "unicode"
)

func main() {

    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter Any Character to Check Digit = ")
    r, _, _ := reader.ReadRune()

    if unicode.IsNumber(r) {
        fmt.Printf("%c is a Digit\n", r)
    } else {
        fmt.Printf("%c is Not a Digit\n", r)
    }
}

SureshMac:GoExamples suresh$ go run charIsDigit1.go
Enter Any Character to Check Digit = 8
8 is a Digit
SureshMac:GoExamples suresh$ go run charIsDigit1.go
Enter Any Character to Check Digit = @
@ is Not a Digit

Go 程序判断字符是否为数字

在这个 Go 示例中，我们将给定的字节字符转换为 Rune（if unicode.IsDigit(rune(ch))），然后使用 IsDigit 函数。

package main

import (
    "bufio"
    "fmt"
    "os"
    "unicode"
)

func main() {

    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter Any Character to Check Digit = ")
    ch, _ := reader.ReadByte()

    if unicode.IsDigit(rune(ch)) {
        fmt.Printf("%c is a Digit\n", ch)
    } else {
        fmt.Printf("%c is Not a Digit\n", ch)
    }
}

SureshMac:GoExamples suresh$ go run charIsDigit2.go
Enter Any Character to Check Digit = 0
0 is a Digit
SureshMac:GoExamples suresh$ go run charIsDigit2.go
Enter Any Character to Check Digit = p
p is Not a Digit

0 到 9 之间的任何数字都称为数字。我们使用 If 条件（if ch >= ‘0’ && ch <= ‘9’）来检查字符是否为数字。

package main

import (
    "bufio"
    "fmt"
    "os"
)

func main() {

    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter Any Character to Check Digit = ")
    ch, _ := reader.ReadByte()

    if ch >= '0' && ch <= '9' {
        fmt.Printf("%c is a Digit\n", ch)
    } else {
        fmt.Printf("%c is Not a Digit\n", ch)
    }
}

SureshMac:GoExamples suresh$ go run charIsDigit3.go
Enter Any Character to Check Digit = 2
2 is a Digit
SureshMac:GoExamples suresh$ go run charIsDigit3.go
Enter Any Character to Check Digit = 8
8 is a Digit

此 Golang 程序使用 ASCII 码（if ch >= 48 && ch <= 57）来检查字符是否为数字。

package main

import (
    "bufio"
    "fmt"
    "os"
)

func main() {

    reader := bufio.NewReader(os.Stdin)

    fmt.Print("Enter Any Character to Check Digit = ")
    ch, _ := reader.ReadByte()

    if ch >= 48 && ch <= 57 {
        fmt.Printf("%c is a Digit\n", ch)
    } else {
        fmt.Printf("%c is Not a Digit\n", ch)
    }
}

SureshMac:GoExamples suresh$ go run charIsDigit4.go
Enter Any Character to Check Digit = 5
5 is a Digit
SureshMac:GoExamples suresh$ go run charIsDigit4.go
Enter Any Character to Check Digit = n
n is Not a Digit