Online fraud refers to the act of cheating others of their property through the Internet, mobile applications, and other electronic channels with false identities, fictional stories, or other deceptive means. If you have been scammed online, you can file a lawsuit in the following ways: 1. Collect evidence: First, you need to collect relevant evidence, including the identity information of the swindler, the means of fraud, the property loss of the victim, and so on. This evidence could be obtained through internet searches, bank records, police records, and other methods. 2. Prepare the complaint: The complaint is an important document for the case. It needs to describe the case in detail, including the identity information of the victim and the swindler, the means of fraud, the loss, the identity information of the defendant, etc. At the same time, he also needed to list all the evidence and explain the source and legitimacy of the evidence. 3. Submit the complaint: Submit the complaint and evidence to the court and submit other documents as required by the court. Waiting for a verdict: The court will hear the case and make a judgment based on the law and evidence. If found guilty, the defendant would have to bear the corresponding legal responsibility. The specific format of an online fraud complaint may vary by region and court. It is recommended to consult the relevant regulations of the local court before filing a lawsuit.