Type-Declaration Characters

I’m having problems passing variables to an API function. I always receive a Type mismatch error. I reproduced the situation in Visual Basic and found that if I used type-declaration characters to declare the problem variables, they were compatible with the API function. So now, I have it working in Visual Basic, but not yet in Delphi. Are there type-declaration characters or something equivalent in Delphi? Here is a sample of my VB code:

'The following vars must be declared with a 'type-declaration character, 'else Type mismatch '(why?...I havea hunch that using 'As String''assigns a NULL value, where 'var$' actually 'assigns an emptystring "")Dim desc$, dt$, con$, fn$, own$, v6$ 'stringsDim fo%, mt% 'integers

The problem doesn’t lie in the API itself, but in Delphi’s wrapper of the API call. What you need to do in addition to looking at the online help is to look at the Delphi source code for the call. Once you see how the call is prototyped, you can pass the appropriate types to it. It takes a lot of the guesswork out of calling API functions.

Share the Post:
Share on facebook
Share on twitter
Share on linkedin


The Latest

homes in the real estate industry

Exploring the Latest Tech Trends Impacting the Real Estate Industry

The real estate industry is changing thanks to the newest technological advancements. These new developments — from blockchain and AI to virtual reality and 3D printing — are poised to change how we buy and sell homes. Real estate brokers, buyers, sellers, wholesale real estate professionals, fix and flippers, and beyond may

man on floor with data

DevX Quick Guide to Data Ingestion

One of the biggest trends of the 21st century is the massive surge in internet usage. With major innovations such as smart technology, social media, and online shopping sites, the internet has become an essential part of everyday life for a large portion of the population. Due to this internet

payment via phone

7 Ways Technology Has Changed Traditional Payments

In today’s digital world, technology has changed how we make payments. From contactless cards to mobile wallets, it’s now easier to pay for goods and services without carrying cash or using a checkbook. This article will look at seven of the most significant ways technology has transformed traditional payment methods.