docs-v2/content/v2.0/reference/flux/stdlib/strings/hasprefix.md

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---
title: strings.hasPrefix() function
description: The strings.hasPrefix() function indicates if a string begins with a specific prefix.
aliases:
- /v2.0/reference/flux/functions/strings/hasprefix/
menu:
v2_0_ref:
name: strings.hasPrefix
parent: Strings
weight: 301
related:
- /v2.0/reference/flux/stdlib/strings/hassuffix
---
The `strings.hasPrefix()` function indicates if a string begins with a specified prefix.
_**Output data type:** Boolean_
```js
import "strings"
strings.hasPrefix(v: "go gopher", t: "go")
// returns true
```
## Parameters
### v
The string value to search.
_**Data type:** String_
### t
The prefix to search for.
_**Data type:** String_
###### Filter based on the presence of a prefix in a column value
```js
import "strings"
data
|> filter(fn:(r) => strings.hasPrefix(v: r.metric, t: "int_" ))
```