Documentation > CMS Template API Library > UploadedFiles > HasKey(String)

             
             if(context.InputForm.UploadedFiles.HasKey("main_image"))
             {
                 // Usually called from post_input.aspx
                 Img img = context.UploadedFiles["my_photo"].Img;
            
                 if (!img.HasError)
                 {
                 // It's likely lasso params from the input would be used for these dimensions
                  ImgResult res = img.CropImage(300, 300, 0, 0, 500, 500);
                  if (res.HasError)
                  {
                     context.Error = "Upload Error cropping image on " + value + " error: " + res.ErrorMessage;           
                   }  
                  }
                 else
                 {
                   context.Error = "Image Error Loading on " + context.UploadedFiles["my_photo"].Path + " error: " + img.ErrorMessage;           
                 }
             }