如何检查字符串中是否有特殊字符或字符是否是 GoLang 中的特殊字符

Question

从输入中读取字符串后，我需要检查其中是否有特殊字符

Answer 1

You can use strings.ContainsAny to see if a rune exists:

package main

import (
  "fmt"
  "strings"
)

func main() {
  fmt.Println(strings.ContainsAny("Hello World", ",|"))
  fmt.Println(strings.ContainsAny("Hello, World", ",|"))
  fmt.Println(strings.ContainsAny("Hello|World", ",|"))
}

Or if you want to check if there are only ASCII characters, you can use strings.IndexFunc:

package main

import (
    "fmt"
    "strings"
)

func main() {
    f := func(r rune) bool {
        return r < 'A' || r > 'z'
    }
    if strings.IndexFunc("HelloWorld", f) != -1 {
        fmt.Println("Found special char")
    }
    if strings.IndexFunc("Hello World", f) != -1 {
        fmt.Println("Found special char")
    }
}

Answer 2

Depending on your definition of special character , the simplest solution would probably to do a for range loop on your string (which yield runes instead of bytes), and for each rune check if it is in your list of allowed/forbidden runes.

See Strings, bytes, runes and characters in Go for more about the relations between string, bytes and runes.

Playground example

package main

var allowed = []rune{'a','b','c','d','e','f','g'}

func haveSpecial(input string) bool {
    for _, char := range input {
        found := false
        for _, c := range allowed {
            if c == char {
                found = true
                break
            }
        }
        if !found {
            return true
        }
    }
    return false
}

func main() {
    cases := []string{
        "abcdef",
        "abc$€f",
    }
    for _, input := range cases {
        if haveSpecial(input) {
            println(input + ": NOK")
        } else {
            println(input + ": OK")
        }
    }
}

Answer 3

You want to use the unicode package, which has a nice function to check for symbols.

https://golang.org/pkg/unicode/#IsSymbol

package main

import (
    "fmt"
    "unicode"
)

func hasSymbol(str string) bool {
    for _, letter := range str {
        if unicode.IsSymbol(letter) {
            return true
        }
    }
    return false
}

func main() {   
    var strs = []string {
        "A quick brown fox",
        "A+quick_brown<fox",
    }

    for _, str := range strs {
        if hasSymbol(str) { 
            fmt.Printf("String '%v' contains symbols.\n", str)
        } else {
            fmt.Printf("String '%v' did not contain symbols.\n", str)   
        }
    }
}

This will provide the following output:

String 'A quick brown fox' did not contain symbols.
String 'A+quick_brown<fox' contains symbols.

Answer 4

I ended up doing something like this

alphabet := "abcdefghijklmnopqrstuvwxyz"
alphabetSplit := strings.Split(alphabet, "")
inputLetters := strings.Split(input, "")

for index, value := range inputLetters {
        special:=1
        for _, char :=range alphabetSplit{
            if char == value {
                special = 0
                break
            }
        }

It might have anything wrong because since I used it to something specific i had to edit to post it here