# useSignTransaction

> @web3auth/modal Vue Composable useSignTransaction | Embedded Wallets

Composable to sign a Solana transaction using the connected wallet from Web3Auth.

### Import

```ts

```

### Usage

```html
<script setup lang="ts">

  const transaction = ref<Transaction | null>(null) // Your transaction object
  const { signTransaction, loading, error, data } = useSignTransaction()

  const handleSign = async () => {
    if (!transaction.value) return
    try {
      await signTransaction(transaction.value)
      // Do something with data.value (signed transaction)
    } catch (e) {
      // Handle error
    }
  }
</script>

<template>
  
    <button @click="handleSign" :disabled="loading">
      {{ loading ? "Signing..." : "Sign Transaction" }}
    </button>
    Error: {{ error.message }}
    Signed Transaction: {{ data }}
  
</template>
```

### Return type

```ts
export type IUseSignTransaction = {
  loading: Ref<boolean>
  error: Ref<Web3AuthError | null>
  data: Ref<string | null>
  signTransaction: (transaction: TransactionOrVersionedTransaction) => Promise<string>
}
```

#### `loading`

`Ref<boolean>`

Indicates if the transaction signing is in progress.

#### `error`

`Ref<Web3AuthError | null>`

Error object if signing fails, otherwise null.

#### `data`

`Ref<string | null>`

The signed transaction as a string, or null if not signed yet.

#### `signTransaction`

`(transaction: TransactionOrVersionedTransaction) => Promise<string>`

Function to sign a Solana transaction. Returns the signed transaction as a string.

## Example

```html
<script setup lang="ts">

  const {
    data: signedTransaction,
    error,
    loading: isPending,
    signTransaction,
  } = useSignTransaction()
  const { accounts, connection } = useSolanaWallet()

  async function submit(event: Event) {
    event.preventDefault()
    const formData = new FormData(event.target as HTMLFormElement)
    const to = formData.get('address') as string
    const value = formData.get('value') as string

    if (!connection.value || !accounts.value || accounts.value.length === 0) return

    const block = await connection.value.getLatestBlockhash()
    const TransactionInstruction = SystemProgram.transfer({
      fromPubkey: new PublicKey(accounts.value[0]),
      toPubkey: new PublicKey(to),
      lamports: Number(value) * LAMPORTS_PER_SOL,
    })

    const transaction = new Transaction({
      blockhash: block.blockhash,
      lastValidBlockHeight: block.lastValidBlockHeight,
      feePayer: new PublicKey(accounts.value[0]),
    }).add(TransactionInstruction)

    signTransaction(transaction)
  }
</script>

<template>
  
    
      Sign Transaction
      <form class="set" @submit.prevent="submit">
        <input name="address" placeholder="Address" required />
        <input name="value" placeholder="Amount (SOL)" type="number" step="0.01" required />
        <button type="submit" :disabled="isPending">{{ isPending ? "Signing..." : "Sign" }}</button>
      </form>
      Signed Transaction: {{ signedTransaction }}
      Error: {{ error.message }}
    
  
</template>
```