如何在 JavaScript 中使用两个按钮进行大写和句子大小写

Question

I have two buttons, one for upper case and another for sentence case, but the upper case button is not not working. My code is below. What am I doing wrong?

 function firstLetterUpper(theString) { var newString = theString.toLowerCase().replace(/([az]+)|([AZ]+)/g, function(c) { return c.toUpperCase() }); return newString; } function convertToSentenceCase() { var theString = document.testForm.theString.value; //alert(theString); var newString = firstLetterUpper(theString); //console.log("Converted: "+newString); document.getElementById('theString').value = newString; } function firstLetterUpper(theString) { var newString = theString.toLowerCase().replace(/(^\\s*\\w|[\\.\\!\\?]\\s*\\w)/g, function(c) { return c.toUpperCase() }); return newString; } function convertToSentenceCase1() { var theString = document.testForm.theString.value; //alert(theString); var newString = firstLetterUpper(theString); //console.log("Converted: "+newString); document.getElementById('theString').value = newString; }

 <form name="testForm"> <textarea name="theString" id="theString" cols="50" rows="5">converts text string to "sentence case" -- capitalizes the first letter of every sentence, and makes the rest lower case. helpful when you need to convert content that is in all caps.</textarea><br> <button onclick="convertToSentenceCase();return false;">Convert to Sentence Case</button> <button onclick="convertToSentenceCase1();return false;">Convert to Upper Case</button> </form>

Answer 1

You have the same name for both of your functions firstLetterUpper .

 function firstLetterUpper(theString) { var newString = theString.toLowerCase().replace(/([az]+)|([AZ]+)/g, function(c) { return c.toUpperCase() }); return newString; } function convertToSentenceCase() { var theString = document.testForm.theString.value; //alert(theString); var newString = firstLetterUpper(theString); //console.log("Converted: "+newString); document.getElementById('theString').value = newString; } function firstLetterUpper1(theString) { var newString = theString.toLowerCase().replace(/(^\\s*\\w|[\\.\\!\\?]\\s*\\w)/g, function(c) { return c.toUpperCase() }); return newString; } function convertToSentenceCase1() { var theString = document.testForm.theString.value; //alert(theString); var newString = firstLetterUpper1(theString); //console.log("Converted: "+newString); document.getElementById('theString').value = newString; }

 <form name="testForm"> <textarea name="theString" id="theString" cols="50" rows="5">converts text string to "sentence case" -- capitalizes the first letter of every sentence, and makes the rest lower case. helpful when you need to convert content that is in all caps.</textarea><br> <button onclick="convertToSentenceCase();return false;">Convert to Sentence Case</button> <button onclick="convertToSentenceCase1();return false;">Convert to Upper Case</button> </form>

Answer 2

Not sure if this is what you wanted. But to make a string uppercase you can use JavaScript's in-built toUpperCase() function.

If you change your function to this it works as expected.

function convertToSentenceCase1() {
  var theString = document.testForm.theString.value;
  //alert(theString);
  var newString = theString.toUpperCase();
  //console.log("Converted: "+newString);
  document.getElementById('theString').value = newString;
}