将切片循环并转化为二维数组

本教程介绍了一种在 Go 中将切片循环并转换为二维数组的方法。我们通过使用内置函数来搜索特定标记 (# INPUTS 和 # OBJECTS) 来定义输入和对象块的边界。然后，我们使用循环来遍历输入块，寻找开始和结束标记，并使用这些标记来提取输入切片。最后，我们将这些切片追加到一个二维数组中，该数组包含所有输入。

我有 17 个 (len(inputstartslice)) 索引切片，它们将生成一系列字符串切片。目前，当我需要将 17 个字符串循环到单个二维字符串数组中时，我的代码仅生成单个字符串切片（单个输入，因为我对位置进行了硬编码，如下所示）。

var inputSlices []string
var inputStartSlice []int
var inputEndSlice []int
var input []string
var inputs [][]string


for v, line := range inputSlices {
  if strings.Contains(line, "{") {
    inputStartSlice = append(inputStartSlice, v)
  }
  if strings.Contains(line, "}") {
    inputEndSlice = append(inputEndSlice, v+1)
  }
}

input = inputSlice[inputStartSlice[3]:inputEndSlice[3]]

inputs = append(inputs, input)
fmt.Println(inouts)

演示

有更好的方法来做到这一点吗？我确信有，如果有人可以帮助我理解更好的方法或详细说明我如何解决我目前陷入的困境..

正确答案

您可以在不使用额外变量的情况下实现相同的目标

package main

import (
    "fmt"
    "log"
    "strings"

    "golang.org/x/exp/slices"
)

func main() {

    var codeslices = []string{
        "# inputs",
        "",
        "input createuserinput {",
        "  username: string!",
        "  email: string!",
        "  password: string!",
        "}",
        "",
        "input authuserinput {",
        "  user: string!",
        "  password: string!",
        "  code: string",
        "}",
        "",
        "input refreshtokensinput{",
        "  refreshtoken: string!",
        "}",
        "",
        "input verifyemailinput {",
        "  token: string!",
        "}",
        "",
        "# objects",
        "",
    }

    //check for boundaries
    inputstart := slices.index(codeslices, "# inputs") //use built-in functions for the search
    if inputstart == -1 {
        log.fatal("# inputs not found")
    }

    objectstart := slices.index(codeslices, "# objects")
    if objectstart == -1 {
        log.fatal("# objects not found")
    }

    inputstart = 0
    var inputs [][]string
    for i := inputstart + 2; i < objectstart-1; i++ {
        if idx := strings.index(codeslices[i], "{"); idx > 0 {
            inputstart = i
            continue
        }
        if idx := slices.index(codeslices[inputstart:], "}"); inputstart > 0 {
            inputs = append(inputs, codeslices[inputstart:i+idx])
            inputstart = 0
        }
    }

    if inputstart > 0 {
        log.fatal("mismatch inputs")
    }

    fmt.printf("%#v\n", inputs)
}

Playground

我已经用更惯用的方式重写了您的代码。检查评论以获取解释。该代码可以工作，但正如 mpx 建议的那样，为了处理任何自定义格式，您必须编写一个分词器和一个词法分析器，以确保正确解析所有内容并处理每个可能的语法错误。

package main

import (
    "fmt"
    "log"
    "strings"

    "golang.org/x/exp/slices"
)

func main() {

    var codeSlices = []string{
        "# INPUTS",
        "",
        "input CreateUserInput {",
        "  username: String!",
        "  email: String!",
        "  password: String!",
        "}",
        "",
        "input AuthUserInput {",
        "  user: String!",
        "  password: String!",
        "  code: String",
        "}",
        "",
        "input RefreshTokensInput{",
        "  refreshToken: String!",
        "}",
        "",
        "input VerifyEmailInput {",
        "  token: String!",
        "}",
        "",
        "# OBJECTS",
        "",
    }

    //Check for boundaries
    inputStart := slices.Index(codeSlices, "# INPUTS") //Use built-in functions for the search
    if inputStart == -1 {
        log.Fatal("# INPUTS not found")
    }

    objectStart := slices.Index(codeSlices, "# OBJECTS")
    if objectStart == -1 {
        log.Fatal("# OBJECTS not found")
    }

    var inputStartSlice []int
    var inputEndSlice []int

    //No need to copy your codeSlices to inputSlice, just go from inputs to objects, this is faster.
    for i := inputStart + 2; i < objectStart-1; i++ {
        if strings.HasSuffix(codeSlices[i], "{") { //HasSuffix is better here, since the { must be the last char
            inputStartSlice = append(inputStartSlice, i)
            continue //No need to check for closing bracket, so we can continue to skip another check
        }
        if codeSlices[i] == "}" { //Direct equality is faster than Contains
            inputEndSlice = append(inputEndSlice, i+1)
        }
    }

    //Check to every open bracket have a closing one
    if len(inputStartSlice) != len(inputEndSlice) {
        log.Fatal("len(inputStartSlice) != len(inputEndSlice)")
    }

    //Concating final results
    var inputs [][]string
    for i := range inputStartSlice {
        inputs = append(inputs, codeSlices[inputStartSlice[i]:inputEndSlice[i]])
    }

    fmt.Println(inputs)
}

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