docs-v2/content/influxdb/cloud/reference/flux/stdlib/strings/index-func.md

title	description	aliases	menu	weight	related
strings.index() function	The strings.index() function returns the index of the first instance of a substring in another string.	/influxdb/cloud/reference/flux/functions/strings/index-func/	influxdb_cloud_ref name parent strings.index Strings	301	/influxdb/cloud/reference/flux/stdlib/strings/indexany/ /influxdb/cloud/reference/flux/stdlib/strings/lastindex/ /influxdb/cloud/reference/flux/stdlib/strings/lastindexany/

The strings.index() function returns the index of the first instance of a substring in a string. If the substring is not present, it returns -1.

Output data type: Integer

import "strings"

strings.index(v: "go gopher", substr: "go")

// returns 0

Parameters

v

The string value to search.

Data type: String

substr

The substring to search for.

Data type: String

Examples

Find the first occurrence of a substring

import "strings"

data
  |> map(fn: (r) => ({
      r with
      the_index: strings.index(v: r.pageTitle, substr: "the")
    })
  )