strings.Index() Function in Golang With Examples Last Updated : 19 Apr, 2020 Comments Improve Suggest changes Like Article Like Report strings.Index() Function in Golang is used to get the first instance of a specified substring. If the substring is not found, then this method will return -1. Syntax: func Index(str, sbstr string) int Here, str is the original string and sbstr is a string whose we want to find index value. Example 1: C // Go program to illustrate the // String Index() Function package main import ( "fmt" "strings" ) // Main function func main() { // Creating and initializing the strings str1 := "Welcome to GeeksforGeeks" str2 := "My name is XYZ" // Displaying strings fmt.Println("String 1: ", str1) fmt.Println("String 2: ", str2) // Using Index() function res1 := strings.Index(str1, "Geeks") res2 := strings.Index(str2, "is") // Displaying the result fmt.Println("\nIndex values:") fmt.Println("Result 1: ", res1) fmt.Println("Result 2: ", res2) } Output: String 1: Welcome to GeeksforGeeks String 2: My name is XYZ Index values: Result 1: 11 Result 2: 8 Example 2: C // Go program to illustrate the // String Index() Function package main import ( "fmt" "strings" ) // Main function func main() { // Using Index() function res1 := strings.Index("GFG", "H") res2 := strings.Index("GeeksforGeeks", "for") // Displaying the result fmt.Println("Result 1: ", res1) fmt.Println("Result 2: ", res2) } Output: Result 1: -1 Result 2: 5 Create Quiz Comment K Kirti_Mangal Follow 0 Improve K Kirti_Mangal Follow 0 Improve Article Tags : Go Language Golang-String Explore OverviewGo Programming Language (Introduction) 7 min read How to Install Go on Windows? 3 min read How to Install Golang on MacOS? 4 min read Hello World in Golang 3 min read FundamentalsIdentifiers in Go Language 3 min read Go Keywords 2 min read Data Types in Go 7 min read Go Variables 9 min read Constants- Go Language 6 min read Go Operators 9 min read Control StatementsGo Decision Making (if, if-else, Nested-if, if-else-if) 5 min read Loops in Go Language 5 min read Switch Statement in Go 2 min read Functions & MethodsFunctions in Go Language 3 min read Variadic Functions in Go 3 min read Anonymous function in Go Language 2 min read main and init function in Golang 2 min read What is Blank Identifier(underscore) in Golang? 3 min read Defer Keyword in Golang 3 min read Methods in Golang 3 min read StructureStructures in Golang 7 min read Nested Structure in Golang 3 min read Anonymous Structure and Field in Golang 3 min read ArraysArrays in Go 7 min read How to Copy an Array into Another Array in Golang? 3 min read How to pass an Array to a Function in Golang? 2 min read SlicesSlices in Golang 14 min read Slice Composite Literal in Go 3 min read How to sort a slice of ints in Golang? 2 min read How to trim a slice of bytes in Golang? 3 min read How to split a slice of bytes in Golang? 3 min read StringsStrings in Golang 7 min read How to Trim a String in Golang? 2 min read How to Split a String in Golang? 3 min read Different ways to compare Strings in Golang 2 min read PointersPointers in Golang 8 min read Passing Pointers to a Function in Go 3 min read Pointer to a Struct in Golang 3 min read Go Pointer to Pointer (Double Pointer) 4 min read Comparing Pointers in Golang 3 min read ConcurrencyGoroutines - Concurrency in Golang 2 min read Select Statement in Go Language 4 min read Multiple Goroutines 2 min read Channel in Golang 7 min read Unidirectional Channel in Golang 2 min read Like