public string ReadArgAsString(int index) { //Cef3Binder.MyCefJs_MetReadArgAsString(this.argPtr,index,) int acutalLen = 0; unsafe { int BUFF_LEN = 256; char *buffHead = stackalloc char[BUFF_LEN]; Cef3Binder.MyCefJs_MetReadArgAsString(argPtr, index, buffHead, BUFF_LEN, ref acutalLen); if (acutalLen > BUFF_LEN) { //read more } return(new string(buffHead, 0, acutalLen)); } }