Explore the power of using Math.pow in JavaScript with UIWebView in iOS

Seeking guidance on how to evaluate a JavaScript string within iOS using the code snippet: 

[self.webView stringByEvaluatingJavaScriptFromString:formula]

The current code in question:

NSString *formula = @"( 1.5 * Math.pow(2, 3) ) / 12";
formula = [NSString stringWithFormat:@"eval('%@')", formula];
NSInteger value = [[self.webView stringByEvaluatingJavaScriptFromString:formula] integerValue];

Encountering an issue with the Math.pow function - when included in the string, it returns an empty result instead of a numeric one from the webView output. In need of assistance to modify the code to successfully handle strings containing Math.pow.

javascriptiosobjective-cuiwebvieweval

Answer №1

Here is where the issue lies:

NSInteger result = [[self.webView stringByEvaluatingJavaScriptFromString:equation] integerValue];

By converting your output to an integer value, it ends up getting rounded off.

The correct approach would be:

float result = [[self.webView stringByEvaluatingJavaScriptFromString:equation] floatValue];

Note the change in data type from result and using floatValue for the string conversion.

Also, just a heads up, you don't necessarily need the eval call.

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