Convert image/png string representation into byte array in C#-CodePudding

From a call to an external API my method receives an image/png as an IRestResponse where the Content property is a string representation.

I need to convert this string representation of image/png into a byte array without saving it first and then going File.ReadAllBytes. How can I achieve this?

CodePudding user response：

You can try a hex string to byte conversion. Here is a method I've used before. Please note that you may have to pad the byte depending on how it comes. The method will throw an error to let you know this. However if whoever sent the image converted it into bytes, then into a hex string (which they should based on what you are saying) then you won't have to worry about padding.

public static byte[] HexToByte(string HexString)
{
    if (HexString.Length % 2 != 0)
        throw new Exception("Invalid HEX");
    byte[] retArray = new byte[HexString.Length / 2];
    for (int i = 0; i < retArray.Length;   i)
    {
        retArray[i] = byte.Parse(HexString.Substring(i * 2, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture);
    }
    return retArray;
}

This might not be the fastest solution by the way, but its a good representation of what needs to happen so you can optimize later.

This is also assuming the string being sent to you is the raw byte converted string. If the sender did anything like a base58 conversion or something else you will need to decode and then use method.

CodePudding user response：

I have found that the IRestResponse from RestSharp actually contains a 'RawBytes' property which is of the response content. This meets my needs and no conversion is necessary!